chore(main): release 0.87.0 (#1261 )

🤖 I have created a release *beep* *boop* --- ## [0.87.0](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.86.0...v0.87.0) (2026-10-07) ### Features * **deps:** Bump the minor group with 2 updates ([#1260](https://github.com/agentclientprotocol/claude-agent-acp/issues/1260)) ([0724b17](0724b17c58)) ### Bug Fixes * async task routing, Monitor tasks, structured task ids, and abandoned tool calls ([#1249](https://github.com/agentclientprotocol/claude-agent-acp/issues/1249)) ([0e83a06](0e83a06c4a)) * settle prompts folded into a task-notification cycle ([#1233](https://github.com/agentclientprotocol/claude-agent-acp/issues/1233)) ([390b0b9](390b0b9f8b)) --- This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please). Co-authored-by: acp-release-bot[bot] <246668977+acp-release-bot[bot]@users.noreply.github.com>
fix: settle prompts folded into a task-notification cycle (#1233 )
2026-11-02 07:23:10 +00:00 · 2026-10-07 15:24:48 +02:00 · 2026-10-07 15:17:38 +02:00 · 2026-10-05 19:23:00 +02:00 · 2026-10-05 18:59:32 +04:00 · 2026-10-05 15:14:44 +02:00
153 changed files with 12475 additions and 1301 deletions
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.82.0"
+  ".": "0.87.0"
 }
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,75 @@
 # Changelog

+## [0.87.0](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.86.0...v0.87.0) (2026-10-07)
+
+
+### Features
+
+* **deps:** Bump the minor group with 2 updates ([#1260](https://github.com/agentclientprotocol/claude-agent-acp/issues/1260)) ([0724b17](https://github.com/agentclientprotocol/claude-agent-acp/commit/0724b17c581e30b1242cfbec7bce44c21df99525))
+
+
+### Bug Fixes
+
+* async task routing, Monitor tasks, structured task ids, and abandoned tool calls ([#1249](https://github.com/agentclientprotocol/claude-agent-acp/issues/1249)) ([0e83a06](https://github.com/agentclientprotocol/claude-agent-acp/commit/0e83a06c4a8825ba654bddf1ab909d1a773942e2))
+* settle prompts folded into a task-notification cycle ([#1233](https://github.com/agentclientprotocol/claude-agent-acp/issues/1233)) ([390b0b9](https://github.com/agentclientprotocol/claude-agent-acp/commit/390b0b9f8bf0cc0aa7d9273a7b614172c916d3a6))
+
+## [0.86.0](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.85.1...v0.86.0) (2026-10-05)
+
+
+### Features
+
+* answer /mcp in chat with the MCP server status and a reconnect ([#1218](https://github.com/agentclientprotocol/claude-agent-acp/issues/1218)) ([190a00f](https://github.com/agentclientprotocol/claude-agent-acp/commit/190a00f68f773315e93630464397944e645616ff))
+* **deps:** Bump @anthropic-ai/claude-agent-sdk to 0.3.287 ([#1224](https://github.com/agentclientprotocol/claude-agent-acp/issues/1224)) ([ddd5f54](https://github.com/agentclientprotocol/claude-agent-acp/commit/ddd5f541879118edb18df7ff09cd6682d455c710))
+
+
+### Bug Fixes
+
+* count a subagent's permission requests as the turn waiting on the user ([#1241](https://github.com/agentclientprotocol/claude-agent-acp/issues/1241)) ([d599333](https://github.com/agentclientprotocol/claude-agent-acp/commit/d599333b722a951553c0efd40a76559b1f32e6ab))
+* drop queued prompts a cancel ends from Claude Code's queue ([#1228](https://github.com/agentclientprotocol/claude-agent-acp/issues/1228)) ([d83f28a](https://github.com/agentclientprotocol/claude-agent-acp/commit/d83f28a4035c5a5e54950fd58c7b73bfc2313664))
+* end a cancelled turn when the force-cancel fires during an update ([#1243](https://github.com/agentclientprotocol/claude-agent-acp/issues/1243)) ([a44c486](https://github.com/agentclientprotocol/claude-agent-acp/commit/a44c486019e98ad478c549c4902e7092f1418d0b))
+* end a closed session's turns before session/close answers ([#1242](https://github.com/agentclientprotocol/claude-agent-acp/issues/1242)) ([b1d6cfc](https://github.com/agentclientprotocol/claude-agent-acp/commit/b1d6cfc6c9fc9ec397e607b68ac100f4d48745b3))
+* end a held turn cancelled mid-followup at its interrupt's idle ([#1229](https://github.com/agentclientprotocol/claude-agent-acp/issues/1229)) ([d3e673b](https://github.com/agentclientprotocol/claude-agent-acp/commit/d3e673b263cf47603a35a50bb3da8b483199f690))
+* excessive message/token_count API calls when probing context window ([#1258](https://github.com/agentclientprotocol/claude-agent-acp/issues/1258)) ([5598efb](https://github.com/agentclientprotocol/claude-agent-acp/commit/5598efbc8ab16720ea79f5c97db40771ad0b317b))
+* replay a session with a Write on the experimental ACP v2 surface ([#1238](https://github.com/agentclientprotocol/claude-agent-acp/issues/1238)) ([22139f7](https://github.com/agentclientprotocol/claude-agent-acp/commit/22139f73c48e621752089a91fb095269493896b1))
+* report a command's exit code only when the tool result says it ([#1252](https://github.com/agentclientprotocol/claude-agent-acp/issues/1252)) ([52a92be](https://github.com/agentclientprotocol/claude-agent-acp/commit/52a92be959f7f8ea90ab08d54bae6900596ab435))
+* restore main-thread agent config option ([#1250](https://github.com/agentclientprotocol/claude-agent-acp/issues/1250)) ([8589a9c](https://github.com/agentclientprotocol/claude-agent-acp/commit/8589a9cf150d8deca6d2f8ef24404d927b3d4828))
+
+## [0.85.1](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.85.0...v0.85.1) (2026-10-01)
+
+
+### Bug Fixes
+
+* answer session/close without waiting for the interrupt reply ([#1216](https://github.com/agentclientprotocol/claude-agent-acp/issues/1216)) ([0c862e2](https://github.com/agentclientprotocol/claude-agent-acp/commit/0c862e29496bb018e7a4400697bd2315dfd5b845))
+* fail turns with unfinished tools ([#1212](https://github.com/agentclientprotocol/claude-agent-acp/issues/1212)) ([7f8d547](https://github.com/agentclientprotocol/claude-agent-acp/commit/7f8d5471e24b981b129b3c9c2d6736c4ba3f8011))
+* restore background task stops on replay instead of showing them as prompts ([#1205](https://github.com/agentclientprotocol/claude-agent-acp/issues/1205)) ([4ffa625](https://github.com/agentclientprotocol/claude-agent-acp/commit/4ffa625977af7e85526b9a3098f4dee5844467b4))
+
+## [0.85.0](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.84.0...v0.85.0) (2026-10-01)
+
+
+### Features
+
+* **deps:** Bump @anthropic-ai/claude-agent-sdk to 0.3.286 ([#1211](https://github.com/agentclientprotocol/claude-agent-acp/issues/1211)) ([f53b0d7](https://github.com/agentclientprotocol/claude-agent-acp/commit/f53b0d7f40bcd0e9bddace85f123ff4851afcb1f))
+
+
+### Bug Fixes
+
+* Adapt to SDK 0.3.284 replay and ultracode changes ([#1208](https://github.com/agentclientprotocol/claude-agent-acp/issues/1208)) ([4af8079](https://github.com/agentclientprotocol/claude-agent-acp/commit/4af807968c7f0813bcb20fe2bcab2370320e9074))
+* send the legacy custom answer key to AIR ([#1210](https://github.com/agentclientprotocol/claude-agent-acp/issues/1210)) ([af0b43d](https://github.com/agentclientprotocol/claude-agent-acp/commit/af0b43de944e36f81343f40b7aa1a96cd48c3218))
+
+## [0.84.0](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.83.0...v0.84.0) (2026-09-28)
+
+
+### Features
+
+* **deps:** update Claude SDK ([#1189](https://github.com/agentclientprotocol/claude-agent-acp/issues/1189)) ([d5e6f33](https://github.com/agentclientprotocol/claude-agent-acp/commit/d5e6f33046614fca4798d49f0c77edba951a6771))
+
+## [0.83.0](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.82.0...v0.83.0) (2026-09-28)
+
+
+### Features
+
+* **deps:** Bump @anthropic-ai/claude-agent-sdk to 0.3.283 ([#1186](https://github.com/agentclientprotocol/claude-agent-acp/issues/1186)) ([49858b5](https://github.com/agentclientprotocol/claude-agent-acp/commit/49858b527397a08d343fe2c148a5fe9e3eb84547))
+
 ## [0.82.0](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.81.2...v0.82.0) (2026-09-28)


--- a/README.md
+++ b/README.md
@@ -17,6 +17,7 @@ This tool implements an ACP agent by using the official [Claude Agent SDK](https
 - Interactive (and background) terminals
 - Custom [Slash commands](https://docs.anthropic.com/en/docs/claude-code/slash-commands)
 - Client MCP servers
+- `/mcp` in the chat: the MCP server status as a list. The adapter runs `/mcp reconnect`, `/mcp enable`, and `/mcp disable` through the SDK control API, because Claude Code refuses them in SDK mode. A reconnect of an ACP server that needs authentication starts MCP OAuth through URL elicitation
 - Session-scoped long-running goals for AIR through the [goal extension](docs/air-extensions.md#goal) under `_meta.jetbrains.air.goal`
 - Structured errors, recovery, and warnings through the opt-in [session failure extension](docs/air-extensions.md#session-failure)
 - Concrete model and effort defaults through the opt-in [recommended config value extension](docs/air-extensions.md#recommended-config-values)
--- a/docs/air-extensions.md
+++ b/docs/air-extensions.md
@@ -164,25 +164,27 @@ Every payload goes into `_meta.jetbrains.air`, next to `version: 1`.
 The adapter merges a payload into an existing `_meta` and keeps the other namespaces.
 The adapter sends these keys only to an AIR client. "AIR" in the Gate column means an AIR client without a further capability.

-| Key                            | Message and field path                                                                | Shape                                                                  | Gate                                           |
-| ------------------------------ | ------------------------------------------------------------------------------------- | ---------------------------------------------------------------------- | ---------------------------------------------- |
-| `capabilities`                 | `initialize` response `_meta.jetbrains.air`                                           | string array                                                           | AIR                                            |
-| `goal`                         | `initialize` response `_meta.jetbrains.air`                                           | `{version: 1, controlMethod, actions}`                                 | AIR                                            |
-| `goal`                         | `session_info_update._meta.jetbrains.air`                                             | goal snapshot or `null`                                                | AIR                                            |
-| `diffPatch`                    | tool call and permission request `content[]` of type `diff`, `_meta.jetbrains.air`    | `{version: 1, format: "git_patch", text}`                              | `diffPatch`                                    |
-| `permission`                   | `session/request_permission` request `_meta.jetbrains.air`                            | `{version: 1, title, description?, defaultToNo?}`                      | AIR                                            |
-| `recommendedValue`             | `model` and effort config options, `_meta.jetbrains.air`                              | option value string                                                    | `recommendedValue`                             |
-| `asyncTasks`                   | Bash `tool_call_update._meta.jetbrains.air`                                           | `{backgrounded: true}`                                                 | `asyncTasks`                                   |
-| `agentFileChangeReportRequest` | `session/prompt` request `_meta.jetbrains.air` (client to agent)                      | `{version: 1, requestId}`                                              | `agentFileChangeReport`                        |
-| `agentFileChangeReport`        | `session_info_update._meta.jetbrains.air`                                             | report object                                                          | `agentFileChangeReport`                        |
-| `sessionFailure`               | `session_info_update._meta.jetbrains.air` or `PromptResponse._meta.jetbrains.air`     | failure record                                                         | `sessionFailure`                               |
-| `commandTitle`                 | Bash and PowerShell tool call `_meta.jetbrains.air`                                   | the `description` input string                                         | AIR                                            |
-| `subagent`                     | Agent and Task tool call `_meta.jetbrains.air`                                        | `true`                                                                 | AIR                                            |
-| `skill`                        | Skill tool call `_meta.jetbrains.air`                                                 | `{name, path?}`                                                        | AIR                                            |
-| `contextCompaction`            | compaction tool call or `compaction_update`, `_meta.jetbrains.air`                    | `{version: 1, trigger?, preTokens?, postTokens?, durationMs?, error?}` | AIR                                            |
-| `customAnswer`                 | elicitation schema property `_meta.jetbrains.air`                                     | `{questionId, isCustomAnswer: true}`                                   | AIR, when the client supports form elicitation |
-| `kind`                         | session mode `_meta.jetbrains.air` and mode config option value `_meta.jetbrains.air` | `standard`, `plan`, `auto_review`, or `full_access`                    | AIR                                            |
-| `fork`                         | `session/fork` request `_meta.jetbrains.air` (client to agent)                        | `{version: 1, messageId, messageFingerprint?, messageOccurrence?}`     | none                                           |
+| Key                            | Message and field path                                                                | Shape                                                                  | Gate                                                                                   |
+| ------------------------------ | ------------------------------------------------------------------------------------- | ---------------------------------------------------------------------- | -------------------------------------------------------------------------------------- |
+| `capabilities`                 | `initialize` response `_meta.jetbrains.air`                                           | string array                                                           | AIR                                                                                    |
+| `goal`                         | `initialize` response `_meta.jetbrains.air`                                           | `{version: 1, controlMethod, actions}`                                 | AIR                                                                                    |
+| `goal`                         | `session_info_update._meta.jetbrains.air`                                             | goal snapshot or `null`                                                | AIR                                                                                    |
+| `diffPatch`                    | tool call and permission request `content[]` of type `diff`, `_meta.jetbrains.air`    | `{version: 1, format: "git_patch", text}`                              | `diffPatch`                                                                            |
+| `permission`                   | `session/request_permission` request `_meta.jetbrains.air`                            | `{version: 1, title, description?, defaultToNo?}`                      | AIR                                                                                    |
+| `recommendedValue`             | `model` and effort config options, `_meta.jetbrains.air`                              | option value string                                                    | `recommendedValue`                                                                     |
+| `asyncTasks`                   | Bash `tool_call_update._meta.jetbrains.air`                                           | `{backgrounded: true}`                                                 | `asyncTasks`                                                                           |
+| `agentFileChangeReportRequest` | `session/prompt` request `_meta.jetbrains.air` (client to agent)                      | `{version: 1, requestId}`                                              | `agentFileChangeReport`                                                                |
+| `agentFileChangeReport`        | `session_info_update._meta.jetbrains.air`                                             | report object                                                          | `agentFileChangeReport`                                                                |
+| `sessionFailure`               | `session_info_update._meta.jetbrains.air` or `PromptResponse._meta.jetbrains.air`     | failure record                                                         | `sessionFailure`                                                                       |
+| `commandTitle`                 | Bash and PowerShell tool call `_meta.jetbrains.air`                                   | the `description` input string                                         | AIR                                                                                    |
+| `subagent`                     | Agent and Task tool call `_meta.jetbrains.air`                                        | `true`                                                                 | AIR                                                                                    |
+| `skill`                        | Skill tool call `_meta.jetbrains.air`                                                 | `{name, path?}`                                                        | AIR                                                                                    |
+| `contextCompaction`            | compaction tool call or `compaction_update`, `_meta.jetbrains.air`                    | `{version: 1, trigger?, preTokens?, postTokens?, durationMs?, error?}` | AIR                                                                                    |
+| `customAnswer`                 | elicitation schema property `_meta.jetbrains.air`                                     | `{questionId, isCustomAnswer: true}`                                   | AIR, when the client supports form elicitation                                         |
+| `kind`                         | session mode `_meta.jetbrains.air` and mode config option value `_meta.jetbrains.air` | `standard`, `plan`, `auto_review`, or `full_access`                    | AIR                                                                                    |
+| `kind`                         | available command `_meta.jetbrains.air` of a skill                                    | `skill`                                                                | AIR, when the skill's `SKILL.md` is found; not for a built-in command or an MCP prompt |
+| `skillPath`                    | available command `_meta.jetbrains.air` of a skill                                    | absolute path of the skill's `SKILL.md`                                | AIR, together with `kind: "skill"`                                                     |
+| `fork`                         | `session/fork` request `_meta.jetbrains.air` (client to agent)                        | `{version: 1, messageId, messageFingerprint?, messageOccurrence?}`     | none                                                                                   |

 ## JetBrains shared keys

@@ -858,10 +860,17 @@ The live test only initializes the SDK. It sends no model prompt.

 ## Async tasks

-Claude can run work in the background, for example a backgrounded Bash command, a workflow, or a monitor.
+Claude can run work in the background, for example a backgrounded Bash command or a workflow.
 The adapter publishes that work as async tasks when the client declares `asyncTasks`.
 Without the capability, the adapter sends no async task update.
 A subagent task (`local_agent`) is not an async task. Native subagent sessions report it.
+A task that a `Monitor` tool call started is not an async task either.
+Monitor streams its output to the model only, so the client gets nothing for it.
+The SDK reports such a task as `local_bash`, so the adapter finds it by the tool of its tool call.
+The `Monitor` tool call stays in the transcript.
+The adapter also ignores a `local_monitor` task.
+A task that a subagent tool call started goes to the subagent session.
+Its spawn, progress and state updates go there also after the subagent finished.

 ### Updates

@@ -872,12 +881,27 @@ A subagent task (`local_agent`) is not an async task. Native subagent sessions r
 - `async_task_state_update` carries `state` (`running`, `paused`, `completed`, `failed`, or `stopped`) and an optional `summary`.
 - The Bash `tool_call_update` of a backgrounded command carries `_meta.jetbrains.air.asyncTasks.backgrounded: true`.
  The card then shows backgrounded work instead of finished work.
+  Only structured data sets the marker: the `backgroundTaskId` of the tool result, a known background task of the tool call, or a `run_in_background` input.
+
+### Task id and output path
+
+An async task comes only from structured data.
+The sources are `tool_use_result.backgroundTaskId` and the SDK `task_started`, `task_updated`, and `task_notification`.
+The text of a tool result never creates a task, because a foreground command can print any text.
+The output path comes from `output_file` of the SDK events when they have it.
+Otherwise the adapter reads the text of the tool result of the task's own tool call.
+It takes only an absolute path that ends with `tasks/<task id>.output`, followed by a period, whitespace or the end of the text.
+The path starts after the nearest `": "` before that end on the same line, so it can hold spaces.
+A path never holds the end of another path.
+A POSIX, a Windows drive, and a UNC path count. A path across a line does not.
+The tool result can come before or after the SDK names the task.
+A subagent tool result has no `tool_use_result`, so this text is the only path source there.

 ### Tool call of a task

 The adapter sends `async_task_spawned` only after it knows the tool call that started the task.
 The SDK gives that id as `tool_use_id` of `task_started`, `task_progress`, or `task_notification`.
-The Bash result of a backgrounded command also gives it.
+The structured Bash result of a backgrounded command also gives it.
 Until the id arrives, the adapter holds the task. It sends no update of a held task.
 The progress and state updates of a held task follow its spawn, in their order.
 A held task gets its spawn without `toolCallId` when it ends first, or when the prompt result ends the turn.
@@ -1204,6 +1228,10 @@ For AIR, the companion field carries `_meta.jetbrains.air.customAnswer`:
 `questionId` names the select field of the same question.
 A client can render the companion as the free-text choice of that question.

+For AIR, the companion field also carries the same value under the root key `_meta._askUserQuestionCustomAnswer`.
+Released AIR versions read only that key.
+A client that is not AIR gets neither key.
+
 ## Session fork point

 AIR can fork a session at one agent message.
@@ -1255,12 +1283,11 @@ The adapter sends the key only to an AIR client.

 These keys moved into the AIR namespace. The adapter sends the new key only to AIR, and the old key to no client.

-| Old key                                                   | New key                                        |
-| --------------------------------------------------------- | ---------------------------------------------- |
-| `initialize._meta.goal`, `session_info_update._meta.goal` | `_meta.jetbrains.air.goal`, same shape         |
-| mode `_meta.kind`, config option value `_meta.kind`       | `_meta.jetbrains.air.kind`                     |
-| elicitation property `_meta._askUserQuestionCustomAnswer` | `_meta.jetbrains.air.customAnswer`, same value |
-| tool call `_meta.contextCompaction`                       | `_meta.jetbrains.air.contextCompaction`        |
+| Old key                                                   | New key                                 |
+| --------------------------------------------------------- | --------------------------------------- |
+| `initialize._meta.goal`, `session_info_update._meta.goal` | `_meta.jetbrains.air.goal`, same shape  |
+| mode `_meta.kind`, config option value `_meta.kind`       | `_meta.jetbrains.air.kind`              |
+| tool call `_meta.contextCompaction`                       | `_meta.jetbrains.air.contextCompaction` |

 The adapter does not send `_meta.claudeCode.title`, `claudeCode.subagent`, `claudeCode.skill`, or `claudeCode.skillPath` to any client.
 AIR reads `_meta.jetbrains.air.commandTitle`, `subagent`, and `skill` instead.
--- a/package-lock.json
+++ b/package-lock.json
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
  "publishConfig": {
    "access": "public"
  },
-  "version": "0.82.0",
+  "version": "0.87.0",
  "description": "An ACP-compatible coding agent powered by the Claude Agent SDK (TypeScript)",
  "main": "dist/lib.js",
  "types": "dist/lib.d.ts",
@@ -65,26 +65,26 @@
    "node": ">=22"
  },
  "dependencies": {
-    "@agentclientprotocol/sdk": "1.5.0",
-    "@anthropic-ai/claude-agent-sdk": "0.3.280",
-    "diff": "^8.0.3",
+    "@agentclientprotocol/sdk": "1.7.0",
+    "@anthropic-ai/claude-agent-sdk": "0.3.287",
+    "diff": "9.0.0",
    "zod": "4.6.5"
  },
  "devDependencies": {
-    "@anthropic-ai/sdk": "0.127.0",
+    "@anthropic-ai/sdk": "0.131.0",
    "@eslint/js": "10.0.1",
    "@tsconfig/node22": "22.0.6",
-    "@types/node": "26.6.2",
-    "@typescript-eslint/eslint-plugin": "8.70.1",
-    "@typescript-eslint/parser": "8.70.1",
+    "@types/node": "26.6.4",
+    "@typescript-eslint/eslint-plugin": "8.71.0",
+    "@typescript-eslint/parser": "8.71.0",
    "ajv": "8.20.0",
    "ajv-formats": "3.0.1",
    "eslint": "10.11.0",
    "eslint-config-prettier": "10.1.8",
-    "globals": "17.12.0",
-    "prettier": "3.9.8",
+    "globals": "17.13.0",
+    "prettier": "3.9.9",
    "ts-node": "10.9.2",
    "typescript": "6.0.3",
-    "vitest": "5.0.1"
+    "vitest": "5.0.3"
  }
 }
--- a/src/acp-agent.ts
+++ b/src/acp-agent.ts
--- a/src/air-extension.ts
+++ b/src/air-extension.ts
@@ -18,8 +18,16 @@ export const AIR_SKILL_KEY = "skill";
 export const AIR_CONTEXT_COMPACTION_KEY = "contextCompaction";
 export const AIR_GOAL_KEY = "goal";
 export const AIR_KIND_KEY = "kind";
+/** The absolute path of the `SKILL.md` of a skill command in `available_commands_update`. */
+export const AIR_SKILL_PATH_KEY = "skillPath";
 export const AIR_PERMISSION_KEY = "permission";
 export const AIR_CUSTOM_ANSWER_KEY = "customAnswer";
+/**
+ * The root `_meta` spelling of {@link AIR_CUSTOM_ANSWER_KEY} that released
+ * AIR versions read. Remove it when the ACP registry no longer serves AIR
+ * versions that read only this spelling.
+ */
+export const LEGACY_AIR_CUSTOM_ANSWER_KEY = "_askUserQuestionCustomAnswer";

 const JETBRAINS_META_KEY = "jetbrains";
 const AIR_META_KEY = "air";
--- a/src/async-tasks.ts
+++ b/src/async-tasks.ts
@@ -43,6 +43,8 @@ type AsyncTask = {

 type TaskIdentity = { taskId?: unknown; task_id?: unknown };

+const MAX_TOOL_RESULT_PATHS = 500;
+
 export type AsyncTaskStarted = TaskIdentity & {
  taskType?: unknown;
  task_type?: unknown;
@@ -112,6 +114,13 @@ export class AsyncTaskRuntime {
   * a command was backgrounded can arrive after its terminal SDK edge.
   */
  private readonly tasks = new Map<string, AsyncTask>();
+  /**
+   * The task output paths in the text of each tool result, by tool call
+   * id. A task whose id and tool call are known takes its output path from
+   * here. The tool result can come before or after the SDK names the task.
+   * The oldest entries are dropped.
+   */
+  private readonly outputPathsByToolCall = new Map<string, string[]>();

  constructor(
    readonly enabled: boolean,
@@ -120,10 +129,13 @@ export class AsyncTaskRuntime {
    /** `notices`: the client can present `notice` updates, so the stop
     *  acknowledgement need not be a transcript line. `routeOf`: the route of
     *  the tasks that a tool call in another session started, for example in
-     *  a native subagent session. */
+     *  a native subagent session. `toolNameOf`: the name of the tool of a tool
+     *  call, or `undefined` when the tool call is unknown. A task that a
+     *  `Monitor` tool call started is ignored. */
    private readonly options: {
      notices?: boolean;
      routeOf?: (toolCallId: string) => Route | undefined;
+      toolNameOf?: (toolCallId: string) => string | undefined;
    } = {},
  ) {}

@@ -132,8 +144,8 @@ export class AsyncTaskRuntime {
    const taskId = taskIdOf(message);
    if (!taskId) return;
    const task = this.task(taskId);
-    if (isSubagentTask(message)) {
-      task.ignored = true;
+    if (isSubagentTask(message) || isMonitorTask(message)) {
+      this.ignore(task);
      return;
    }

@@ -163,8 +175,8 @@ export class AsyncTaskRuntime {
    const taskId = taskIdOf(message);
    if (!taskId) return;
    const task = this.task(taskId);
-    if (isSubagentTask(message)) {
-      task.ignored = true;
+    if (isSubagentTask(message) || isMonitorTask(message)) {
+      this.ignore(task);
      return;
    }

@@ -330,8 +342,9 @@ export class AsyncTaskRuntime {
      live.add(taskId);
      const task = this.task(taskId);
      if (task.ignored || isTerminal(task.state)) continue;
-      if (field(item, "taskType", "task_type") === "local_agent") {
-        task.ignored = true;
+      const levelTaskType = field(item, "taskType", "task_type");
+      if (levelTaskType === "local_agent" || levelTaskType === "local_monitor") {
+        this.ignore(task);
        continue;
      }
      if (!task.startedObserved) {
@@ -423,6 +436,41 @@ export class AsyncTaskRuntime {
    );
  }

+  /** Whether a task of the tool call went to the background, so the client gets it. */
+  isBackgroundedToolCall(toolCallId: string): boolean {
+    for (const task of this.tasks.values()) {
+      if (task.toolCallId === toolCallId && !task.ignored && (task.announced || task.held)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Reads the tool results in `content` for the output path of a known task.
+   * Only a path that ends with `tasks/<task id>.output` in the result of
+   * the task's own tool call counts. A tool result never creates a task.
+   */
+  async toolResults(content: unknown): Promise<void> {
+    if (!this.enabled || !Array.isArray(content)) return;
+    for (const result of content.flatMap(toolResultBlock)) {
+      const text = textContent(result.content);
+      const paths = text ? taskOutputPaths(text) : [];
+      if (paths.length === 0) continue;
+      this.outputPathsByToolCall.delete(result.toolUseId);
+      this.outputPathsByToolCall.set(result.toolUseId, paths);
+      if (this.outputPathsByToolCall.size > MAX_TOOL_RESULT_PATHS) {
+        const oldest = this.outputPathsByToolCall.keys().next().value;
+        if (oldest !== undefined) this.outputPathsByToolCall.delete(oldest);
+      }
+      for (const task of this.tasks.values()) {
+        if (task.toolCallId !== result.toolUseId || task.ignored || task.outputFilePath) continue;
+        this.mergeToolResultPath(task);
+        if (task.outputFilePath && task.announced) await this.publishMetadata(task);
+      }
+    }
+  }
+
  /**
   * Sends the spawn of each held task without a tool call id. The prompt
   * result ends the model turn, and the result of the tool call that started a
@@ -437,6 +485,18 @@ export class AsyncTaskRuntime {

  clear(): void {
    this.tasks.clear();
+    this.outputPathsByToolCall.clear();
+  }
+
+  /**
+   * Marks a task that the client never sees. Only a task that is not announced
+   * can become ignored, so the client never holds a task without its end.
+   */
+  private ignore(task: AsyncTask): void {
+    if (task.announced) return;
+    task.ignored = true;
+    task.held = false;
+    task.deferred = [];
  }

  private task(taskId: string): AsyncTask {
@@ -484,6 +544,7 @@ export class AsyncTaskRuntime {
    this.mergeOutputFilePath(task, message);
    const toolCallId = nonBlankString(field(message, "toolCallId", "tool_use_id"));
    if (toolCallId) task.toolCallId = toolCallId;
+    this.mergeToolResultPath(task);
  }

  /** Keeps the first tool call id that a later SDK message brings. */
@@ -492,6 +553,17 @@ export class AsyncTaskRuntime {
    value: { toolCallId?: unknown; tool_use_id?: unknown },
  ): void {
    task.toolCallId ??= nonBlankString(field(value, "toolCallId", "tool_use_id"));
+    this.mergeToolResultPath(task);
+  }
+
+  /**
+   * Takes the output path from the result of the task's tool call when no
+   * structured source gave one. A structured path later replaces it.
+   */
+  private mergeToolResultPath(task: AsyncTask): void {
+    if (task.outputFilePath || !task.toolCallId) return;
+    const paths = this.outputPathsByToolCall.get(task.toolCallId);
+    if (paths) task.outputFilePath = outputFilePathOf(paths, task.id);
  }

  /** Sends an update of an announced task. A held task sends it after its spawn. */
@@ -535,12 +607,22 @@ export class AsyncTaskRuntime {
   * backgrounded command. A held task gets its spawn without the id when it
   * ends first, or when the prompt result ends the model turn
   * ({@link releaseHeld}). No guess by the command text binds a task.
+   *
+   * A task that a `Monitor` tool call started is ignored: Monitor streams its
+   * output to the model only, so the task has nothing for the client. The
+   * tool_use streams before the tool runs, so the tool name is known when the
+   * spawn has the tool call id.
   */
  private async announce(
    task: AsyncTask,
    options: { withoutToolCall?: boolean } = {},
  ): Promise<void> {
    if (task.announced || task.ignored) return;
+    const toolName = task.toolCallId ? this.options.toolNameOf?.(task.toolCallId) : undefined;
+    if (toolName !== undefined && HIDDEN_TASK_TOOLS.has(toolName)) {
+      this.ignore(task);
+      return;
+    }
    if (!task.toolCallId && !options.withoutToolCall && !isTerminal(task.state)) {
      task.held = true;
      return;
@@ -692,7 +774,11 @@ function recordPublished(task: AsyncTask, fields: Record<string, unknown>): void
  }
 }

-/** Recovers background Bash lifecycle data exposed only on its tool result. */
+/**
+ * Recovers a background Bash task from the structured `backgroundTaskId` of
+ * its tool result. The text of a tool result never gives a task id: a
+ * foreground command can print any text.
+ */
 export function backgroundBashTaskFromToolResult(
  content: unknown,
  toolUseResult: unknown,
@@ -704,12 +790,7 @@ export function backgroundBashTaskFromToolResult(
  if (bashResults.length === 0) return undefined;

  const backgroundResults = structuredBackgroundResults(toolUseResult, toolUses);
-  const distinctTaskIds = new Set([
-    ...backgroundResults.map((result) => result.taskId),
-    ...bashResults
-      .map((result) => backgroundTaskIdFromText(result.content))
-      .filter((taskId): taskId is string => taskId !== undefined),
-  ]);
+  const distinctTaskIds = new Set(backgroundResults.map((result) => result.taskId));
  if (distinctTaskIds.size !== 1) return undefined;
  const taskId = [...distinctTaskIds][0];
  if (!taskId) return undefined;
@@ -743,15 +824,36 @@ export function backgroundBashTaskFromToolResult(
  };
 }

-function backgroundTaskIdFromText(content: unknown): string | undefined {
-  const text = textContent(content);
-  if (!text) return undefined;
-  const marker = "Command running in background with ID: ";
-  const start = text.indexOf(marker);
-  if (start < 0) return undefined;
-  const valueStart = start + marker.length;
-  const valueEnd = text.indexOf(".", valueStart);
-  return valueEnd < 0 ? undefined : nonBlankString(text.slice(valueStart, valueEnd));
+/**
+ * The Bash tool calls in `content` whose command went to the background. Only
+ * structured data counts: the task from the structured tool result, a task
+ * that the runtime knows for the tool call, or a `run_in_background` input of
+ * a call that did not fail.
+ */
+export function backgroundedBashToolCallIds(
+  content: unknown,
+  toolUses: Record<string, { name: string; input: unknown }>,
+  runtime: AsyncTaskRuntime,
+  structuredTask?: AsyncTaskStarted,
+): Set<string> {
+  const ids = new Set<string>();
+  if (!runtime.enabled || !Array.isArray(content)) return ids;
+  const structuredToolCallId = structuredTask
+    ? nonBlankString(field(structuredTask, "toolCallId", "tool_use_id"))
+    : undefined;
+  for (const result of content.flatMap(toolResultBlock)) {
+    const toolUse = toolUses[result.toolUseId];
+    if (toolUse?.name !== "Bash") continue;
+    const input = isRecord(toolUse.input) ? toolUse.input : undefined;
+    if (
+      result.toolUseId === structuredToolCallId ||
+      runtime.isBackgroundedToolCall(result.toolUseId) ||
+      (input?.run_in_background === true && !result.isError)
+    ) {
+      ids.add(result.toolUseId);
+    }
+  }
+  return ids;
 }

 function structuredBackgroundResults(
@@ -783,27 +885,73 @@ function structuredBackgroundResults(
  return results;
 }

-function toolResultBlock(value: unknown): { toolUseId: string; content?: unknown }[] {
+function toolResultBlock(
+  value: unknown,
+): { toolUseId: string; content?: unknown; isError: boolean }[] {
  if (!isRecord(value) || value.type !== "tool_result") return [];
  const toolUseId = nonBlankString(field(value, "toolUseId", "tool_use_id"));
-  return toolUseId ? [{ toolUseId, content: value.content }] : [];
+  return toolUseId
+    ? [
+        {
+          toolUseId,
+          content: value.content,
+          isError: field(value, "isError", "is_error") === true,
+        },
+      ]
+    : [];
 }

 function asyncTaskOutputFilePath(content: unknown, taskId: string): string | undefined {
  const text = textContent(content);
-  if (!text) return undefined;
-  const marker = "Output is being written to: ";
-  const start = text.indexOf(marker);
-  if (start < 0) return undefined;
-  const valueStart = start + marker.length;
-  const valueEnd = text.indexOf(". You will be notified", valueStart);
-  if (valueEnd < 0) return undefined;
-  const path = text.slice(valueStart, valueEnd).trim();
-  const expectedPosixSuffix = `/tasks/${taskId}.output`;
-  const expectedWindowsSuffix = `\\tasks\\${taskId}.output`;
-  return path.endsWith(expectedPosixSuffix) || path.endsWith(expectedWindowsSuffix)
-    ? path
-    : undefined;
+  return text ? outputFilePathOf(taskOutputPaths(text), taskId) : undefined;
+}
+
+/**
+ * The end of a task output path: `tasks/<id>.output`, followed by a sentence
+ * period, whitespace or the end of the text. Claude Code writes the output of
+ * a background task there.
+ */
+const TASK_OUTPUT_SUFFIX = /[/\\]tasks[/\\][^\s/\\]+?\.output(?=\.(?!\w)|\s|$)/g;
+/** An absolute POSIX, Windows drive or UNC path. */
+const ABSOLUTE_PATH = /^(?:\/|[A-Za-z]:[\\/]|\\\\)/;
+
+/**
+ * The task output paths in a tool result text. Each text of Claude Code puts
+ * the path after "Output is being written to: ", so a path starts after the
+ * nearest `": "` before its end. A drive colon has no space after it, so a
+ * path can hold spaces and a drive. The search for the start stops at a line
+ * break and at the end of the previous path end, so a path never crosses a
+ * line or holds another path. Each character is read at most once, so the
+ * parse is linear in the text length. A path that is not absolute does not
+ * count.
+ */
+function taskOutputPaths(text: string): string[] {
+  const paths: string[] = [];
+  let previousEnd = 0;
+  for (const match of text.matchAll(TASK_OUTPUT_SUFFIX)) {
+    const end = match.index + match[0].length;
+    let start = -1;
+    for (let i = match.index - 1; i >= previousEnd; i--) {
+      const char = text[i];
+      if (char === "\n" || char === "\r") break;
+      if (char === ":" && text[i + 1] === " ") {
+        start = i + 2;
+        break;
+      }
+    }
+    previousEnd = end;
+    if (start < 0) continue;
+    const path = text.slice(start, end);
+    if (ABSOLUTE_PATH.test(path)) paths.push(path);
+  }
+  return paths;
+}
+
+/** The output path of the task `taskId` among the paths, if one names it. */
+function outputFilePathOf(paths: readonly string[], taskId: string): string | undefined {
+  const posix = `/tasks/${taskId}.output`;
+  const windows = `\\tasks\\${taskId}.output`;
+  return paths.find((path) => path.endsWith(posix) || path.endsWith(windows));
 }

 function textContent(value: unknown): string | undefined {
@@ -834,6 +982,13 @@ function isBackgroundTask(isBackgrounded: unknown, taskType: unknown): boolean {
  return taskType !== "local_bash" && taskType !== "local_agent";
 }

+/** The tools whose async tasks the client never sees. */
+const HIDDEN_TASK_TOOLS = new Set(["Monitor"]);
+
+function isMonitorTask(message: AsyncTaskStarted): boolean {
+  return field(message, "taskType", "task_type") === "local_monitor";
+}
+
 function isSubagentTask(message: AsyncTaskStarted): boolean {
  return (
    field(message, "subagentType", "subagent_type") !== undefined ||
--- a/src/clear-context-coordinator.ts
+++ b/src/clear-context-coordinator.ts
@@ -5,7 +5,7 @@ import type {
  PermissionMode,
  SDKUserMessage,
 } from "@anthropic-ai/claude-agent-sdk";
-import { DEFAULT_MODEL_ID } from "./session-config-ids.js";
+import { DEFAULT_AGENT_ID, DEFAULT_MODEL_ID } from "./session-config-ids.js";

 export type ClearContextReset = {
  toolUseId: string;
@@ -37,6 +37,7 @@ export type ClearContextSession<Turn extends ClearContextTurn = ClearContextTurn
  accumulatedModelUsage?: Record<string, Usage>;
  models: { currentModelId: string };
  configOptions: SessionConfigOption[];
+  currentAgent: string;
  fastModeEnabled: boolean;
  effortPinnedLevel?: string;
  activeTurn?: Turn | null;
@@ -88,6 +89,7 @@ function restartParams<Session extends ClearContextSession>(session: Session): N
          ...(session.models.currentModelId !== DEFAULT_MODEL_ID
            ? { model: session.models.currentModelId }
            : {}),
+          ...(session.currentAgent !== DEFAULT_AGENT_ID ? { agent: session.currentAgent } : {}),
          ...(session.effortPinnedLevel !== undefined
            ? { effort: session.effortPinnedLevel as EffortLevel }
            : {}),
--- a/src/diff.ts
+++ b/src/diff.ts
@@ -1,4 +1,5 @@
 import { ToolCallContent, ToolCallLocation } from "@agentclientprotocol/sdk";
+import type * as v2 from "@agentclientprotocol/sdk/experimental/v2";
 import { structuredPatch } from "diff";
 import { constants } from "node:fs";
 import { type FileHandle, open } from "node:fs/promises";
@@ -73,6 +74,28 @@ interface EditPreviewInput {
 /** The kind of file change that a git patch describes. */
 type FileChange = "create" | "update";

+/** A file change and the hunks of its git patch. */
+interface FilePatch {
+  change: FileChange;
+  hunks: PatchHunk[];
+}
+
+/**
+ * The diff that carries an exact patch: AIR's `diffPatch` extension of a v1
+ * diff, or an ACP v2 diff.
+ */
+export type PatchForm = "air" | "v2";
+
+/**
+ * How a git patch names its file. `git` is git's own form: the leading slash
+ * dropped and the `a/` and `b/` prefixes added. `absolute` is the form of an
+ * ACP v2 `git_patch`, whose paths must be absolute: the path itself.
+ */
+type GitPatchPaths = "git" | "absolute";
+
+/** An ACP v2 diff, as tool call content. */
+type V2DiffContent = v2.Diff & { type: "diff" };
+
 /**
 * Builds the exact patch shown before Claude runs an Edit or Write tool.
 *
@@ -85,8 +108,8 @@ type FileChange = "create" | "update";
 * normalizes quotes or fails.
 *
 * A Write always gets content that shows the change: the patch, the standard
- * diff of a text that cannot have an exact patch, or a notice that the Write
- * overwrites a file that the adapter cannot show.
+ * diff (in v2, the change alone) of a text that cannot have an exact patch, or
+ * a notice that the Write overwrites a file that the adapter cannot show.
 *
 * The preview uses the tool input as it is. Claude can still remove the
 * trailing whitespace of a line before it writes. The PostToolUse hook then
@@ -96,6 +119,7 @@ export async function previewPatchContent(
  toolName: string,
  input: Record<string, unknown>,
  cwd?: string,
+  form: PatchForm = "air",
 ): Promise<ToolCallContent[] | undefined> {
  if (toolName === "Edit") {
    const edit = input as EditPreviewInput;
@@ -119,7 +143,7 @@ export async function previewPatchContent(
      if (oldText !== null && (oldText.trim() !== "" || oldText.includes("\uFEFF"))) {
        return undefined;
      }
-      return optionalContent(filePatch(filePath, oldText, newString)?.content);
+      return exactPatch(filePath, oldText, newString, form);
    }
    if (oldText === null) return undefined;
    const occurrences = oldText.split(oldString).length - 1;
@@ -128,7 +152,7 @@ export async function previewPatchContent(
      return undefined;
    }
    const newText = replacedText(oldText, oldString, newString, edit.replace_all === true);
-    return optionalContent(filePatch(filePath, oldText, newText)?.content);
+    return exactPatch(filePath, oldText, newText, form);
  }

  if (toolName === "Write") {
@@ -154,11 +178,13 @@ export async function previewPatchContent(
    }
    if (oldText === content) return undefined;
    const standard: ToolCallContent[] = [
-      { type: "diff", path: write.file_path, oldText, newText: content },
+      form === "v2"
+        ? v2DiffContent(filePath, oldText === null ? "create" : "update")
+        : { type: "diff", path: write.file_path, oldText, newText: content },
    ];
    if (!isPatchableText(content)) return standard;
    // A dense change can exceed the diff budget. The approval then shows the standard diff.
-    return optionalContent(filePatch(filePath, oldText, content)?.content) ?? standard;
+    return exactPatch(filePath, oldText, content, form) ?? standard;
  }

  return undefined;
@@ -217,6 +243,7 @@ function replacedText(
 */
 export async function patchUpdateFromDiffToolResponse(
  toolResponse: unknown,
+  form: PatchForm = "air",
 ): Promise<{ content: ToolCallContent[]; locations: ToolCallLocation[] } | undefined> {
  if (!toolResponse || typeof toolResponse !== "object") return undefined;
  const response = toolResponse as DiffToolResponse;
@@ -249,10 +276,10 @@ export async function patchUpdateFromDiffToolResponse(
  const newText = await readPatchSource(response.filePath);
  if (typeof newText !== "string" || newText.startsWith("\uFEFF")) return undefined;
  if (response.type === "create" && newText !== response.content) return undefined;
-  const patch = filePatch(response.filePath, oldText, newText);
+  const patch = filePatch(oldText, newText);
  if (!patch) return undefined;
  return {
-    content: [patch.content],
+    content: [patchContent(response.filePath, patch, form)],
    // A created file keeps the location of its Write tool call.
    locations:
      oldText === null
@@ -341,27 +368,83 @@ export function toolUpdateFromDiffToolResponse(toolResponse: unknown): {
  return result;
 }

+/**
+ * The ACP v2 diff of a finished Edit or Write: the exact patch of
+ * {@link patchUpdateFromDiffToolResponse} when it can be built, else the
+ * change with a patch from what the toolResponse holds.
+ *
+ * The fallback patch of an update comes from the `structuredPatch`, which is
+ * display data (see {@link patchUpdateFromDiffToolResponse}). That is enough
+ * for a v2 patch, which is renderable text, not a patch to apply. An update
+ * without hunks, such as one whose previous content was too large to diff,
+ * gets the change alone. An Edit with an empty `old_string` reports the same
+ * response for a created file and a filled empty one, so it gets no diff.
+ */
+export async function v2UpdateFromDiffToolResponse(toolResponse: unknown): Promise<{
+  content?: ToolCallContent[];
+  locations?: ToolCallLocation[];
+}> {
+  const exact = await patchUpdateFromDiffToolResponse(toolResponse, "v2");
+  if (exact) return exact;
+  if (!toolResponse || typeof toolResponse !== "object") return {};
+  const response = toolResponse as DiffToolResponse;
+  const filePath = response.filePath;
+  if (typeof filePath !== "string") return {};
+  if (response.type === "create") {
+    const hunk =
+      typeof response.content === "string" && isPatchableText(response.content)
+        ? wholeFileHunk(response.content)
+        : undefined;
+    return {
+      content: [v2DiffContent(filePath, "create", hunk && [hunk])],
+      locations: [{ path: filePath }],
+    };
+  }
+  if (response.type === undefined && response.oldString === "" && response.originalFile === "") {
+    return {};
+  }
+  // A Write whose content is the previous text changed nothing.
+  if (response.type === "update" && response.content === response.originalFile) return {};
+  const hunks =
+    Array.isArray(response.structuredPatch) && response.structuredPatch.length > 0
+      ? response.structuredPatch
+      : undefined;
+  return {
+    content: [v2DiffContent(filePath, "update", hunks)],
+    locations: hunks
+      ? hunks.map(({ newStart }) => ({ path: filePath, line: newStart }))
+      : [{ path: filePath }],
+  };
+}
+
 /**
 * The text of one git patch for `filePath`.
 *
- * The headers follow `git diff`: the path loses its leading slash, gets the
- * `a/` and `b/` prefixes, and is quoted when git would quote it. A created
- * file gets its mode line and a `/dev/null` side.
+ * The headers follow `git diff`: the path is quoted when git would quote it,
+ * and a created file gets its mode line and a `/dev/null` side. With `git`
+ * paths, the path loses its leading slash and gets the `a/` and `b/` prefixes.
 */
-export function gitPatchText(filePath: string, change: FileChange, hunks: PatchHunk[]): string {
+export function gitPatchText(
+  filePath: string,
+  change: FileChange,
+  hunks: PatchHunk[],
+  paths: GitPatchPaths = "git",
+): string {
  return [
-    ...gitPatchHeader(filePath, change),
+    ...gitPatchHeader(filePath, change, paths),
    ...hunks.flatMap((hunk) => [hunkHeader(hunk), ...hunk.lines]),
    "",
  ].join("\n");
 }

-function gitPatchHeader(filePath: string, change: FileChange): string[] {
-  // git drops one leading slash of an absolute path; a Windows path gets
-  // forward slashes so the header names the same file on every platform.
-  const name = filePath.replaceAll("\\", "/").replace(/^\/+/u, "");
-  const oldName = quoteGitPath("a/", name);
-  const newName = quoteGitPath("b/", name);
+function gitPatchHeader(filePath: string, change: FileChange, paths: GitPatchPaths): string[] {
+  // A Windows path gets forward slashes so the header names the same file on
+  // every platform.
+  const slashed = filePath.replaceAll("\\", "/");
+  // git drops one leading slash of an absolute path.
+  const name = paths === "git" ? slashed.replace(/^\/+/u, "") : slashed;
+  const oldName = quoteGitPath(paths === "git" ? "a/" : "", name);
+  const newName = quoteGitPath(paths === "git" ? "b/" : "", name);
  // git ends a ---/+++ name that contains a space with a tab, for GNU patch.
  const tab = name.includes(" ") ? "\t" : "";
  return [
@@ -481,18 +564,14 @@ function textLines(text: string): string[] {
 }

 /**
- * The git patch of a file change and its hunks. Returns undefined when
- * nothing changed or the diff runs out of its time budget.
+ * The patch of a change from `oldText`, null for a missing file, to
+ * `newText`. Returns undefined when nothing changed or the diff runs out of
+ * its time budget.
 */
-function filePatch(
-  filePath: string,
-  oldText: string | null,
-  newText: string,
-): { content: ToolCallContent; hunks: PatchHunk[] } | undefined {
+function filePatch(oldText: string | null, newText: string): FilePatch | undefined {
  const hunks = diffHunks(oldText, newText);
  if (!hunks || hunks.length === 0) return undefined;
-  const change = oldText === null ? "create" : "update";
-  return { content: patchContent(filePath, gitPatchText(filePath, change, hunks)), hunks };
+  return { change: oldText === null ? "create" : "update", hunks };
 }

 /**
@@ -553,8 +632,22 @@ function isPatchableText(text: string): boolean {
  );
 }

-function optionalContent(content: ToolCallContent | undefined): ToolCallContent[] | undefined {
-  return content ? [content] : undefined;
+/** The exact patch content of a change, or undefined when it has no patch. */
+function exactPatch(
+  filePath: string,
+  oldText: string | null,
+  newText: string,
+  form: PatchForm,
+): ToolCallContent[] | undefined {
+  const patch = filePatch(oldText, newText);
+  return patch && [patchContent(filePath, patch, form)];
+}
+
+/** The content that carries a patch, in the given form. */
+function patchContent(filePath: string, patch: FilePatch, form: PatchForm): ToolCallContent {
+  return form === "v2"
+    ? v2DiffContent(filePath, patch.change, patch.hunks)
+    : airPatchContent(filePath, patch);
 }

 /**
@@ -563,7 +656,7 @@ function optionalContent(content: ToolCallContent | undefined): ToolCallContent[
 * `oldText: null` and `newText: ""` only satisfy the ACP schema. The adapter
 * sends this form only to a client that advertised `diffPatch`.
 */
-function patchContent(filePath: string, text: string): ToolCallContent {
+function airPatchContent(filePath: string, { change, hunks }: FilePatch): ToolCallContent {
  return {
    type: "diff",
    path: filePath,
@@ -572,11 +665,39 @@ function patchContent(filePath: string, text: string): ToolCallContent {
    _meta: withAirMeta(undefined, AIR_DIFF_PATCH_CAPABILITY, {
      version: 1,
      format: "git_patch",
-      text,
+      text: gitPatchText(filePath, change, hunks),
    }),
  };
 }

+/**
+ * The ACP v2 diff of a change to the text file `filePath`: the change and,
+ * given hunks, its git patch.
+ *
+ * The agent builds tool call content in v1 types, and v1 cannot express a v2
+ * diff, so the diff travels as v1 content. Nothing in the agent reads inside a
+ * diff, and only a v2 client gets one: the v2 surface sends it as it is
+ * (`src/v2/tool-call.ts`).
+ */
+export function v2DiffContent(
+  filePath: string,
+  change: FileChange,
+  hunks?: PatchHunk[],
+): ToolCallContent {
+  const fileChange: v2.DiffChange =
+    change === "create"
+      ? { operation: "add", path: filePath, fileType: "text" }
+      : { operation: "modify", path: filePath, fileType: "text" };
+  const diff: V2DiffContent = {
+    type: "diff",
+    changes: [fileChange],
+    ...(hunks?.length
+      ? { patch: { format: "git_patch", text: gitPatchText(filePath, change, hunks, "absolute") } }
+      : {}),
+  };
+  return diff as unknown as ToolCallContent;
+}
+
 function resolveToolPath(filePath: string, cwd?: string): string {
  return path.isAbsolute(filePath) ? filePath : path.resolve(cwd ?? process.cwd(), filePath);
 }
--- a/src/elicitation.ts
+++ b/src/elicitation.ts
@@ -12,7 +12,11 @@ import type {
  AskUserQuestionInput,
  AskUserQuestionOutput,
 } from "@anthropic-ai/claude-agent-sdk/sdk-tools.js";
-import { AIR_CUSTOM_ANSWER_KEY, withAirMeta } from "./air-extension.js";
+import {
+  AIR_CUSTOM_ANSWER_KEY,
+  LEGACY_AIR_CUSTOM_ANSWER_KEY,
+  withAirMeta,
+} from "./air-extension.js";

 /**
 * Bridges between the Claude Agent SDK's elicitation/dialog callbacks and ACP's
@@ -204,6 +208,7 @@ export function askUserQuestionsToCreateRequest(
      ? { type: "array", title, description, items: { anyOf: options } }
      : { type: "string", title, description, oneOf: options };

+    const customAnswer = { questionId: questionFieldKey(index), isCustomAnswer: true };
    properties[questionCustomFieldKey(index)] = {
      type: "string",
      title: "Other",
@@ -211,13 +216,15 @@ export function askUserQuestionsToCreateRequest(
        ? "Type your own answer to add to your selection above (optional)."
        : "Type your own answer, or add a note to the option you chose above (optional).",
      // Marks the field as the custom answer companion of a select question,
-      // under `_meta.jetbrains.air.customAnswer`. Only AIR gets the marker.
+      // under `_meta.jetbrains.air.customAnswer` and under the root key that
+      // released AIR versions read. Only AIR gets the marker.
      ...(airClient
        ? {
-            _meta: withAirMeta(undefined, AIR_CUSTOM_ANSWER_KEY, {
-              questionId: questionFieldKey(index),
-              isCustomAnswer: true,
-            }),
+            _meta: withAirMeta(
+              { [LEGACY_AIR_CUSTOM_ANSWER_KEY]: customAnswer },
+              AIR_CUSTOM_ANSWER_KEY,
+              customAnswer,
+            ),
          }
        : {}),
    };
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,7 +1,8 @@
 #!/usr/bin/env node

-import { claudeCliPath, runAcp } from "./acp-agent.js";
+import { claudeCliPath } from "./acp-agent.js";
 import { applyManagedPolicyEnv } from "./managed-policy.js";
+import { serveAcp } from "./serve.js";
 import packageJson from "../package.json" with { type: "json" };
 import { appendFileSync, mkdirSync } from "node:fs";
 import { join } from "node:path";
@@ -82,10 +83,13 @@ if (process.argv.includes("--cli")) {
    : undefined;
  logger?.log("Claude ACP started");

-  const { connection, agent } = runAcp(logger);
+  // The draft ACP v2 is opt-in while it is a draft.
+  const acp = serveAcp(logger, {
+    experimentalV2: process.env.CLAUDE_AGENT_ACP_EXPERIMENTAL_V2 === "1",
+  });

  async function shutdown() {
-    await agent.dispose().catch((err) => {
+    await acp.dispose().catch((err) => {
      console.error("Error during cleanup:", err);
    });
    process.exit(0);
@@ -94,7 +98,7 @@ if (process.argv.includes("--cli")) {
  // Exit cleanly when the ACP connection closes (e.g. stdin EOF, transport
  // error). Without this, `process.stdin.resume()` keeps the event loop
  // alive indefinitely, causing orphan process accumulation in oneshot mode.
-  connection.closed.then(shutdown);
+  acp.closed.then(shutdown);

  process.on("SIGTERM", shutdown);
  process.on("SIGINT", shutdown);
--- a/src/mcp-command.ts
+++ b/src/mcp-command.ts
@@ -0,0 +1,388 @@
+import type { AvailableCommand } from "@agentclientprotocol/sdk";
+import type { McpServerStatus, Query } from "@anthropic-ai/claude-agent-sdk";
+import { escapeMarkdown } from "./usage-markdown.js";
+import { raceTimeoutAndAbort } from "./utils.js";
+
+/** The `/mcp` entry of `available_commands_update`. The adapter shows the
+ *  servers as a list, and runs a reconnect, an enable, or a disable through
+ *  the SDK control API. */
+export const MCP_AVAILABLE_COMMAND: AvailableCommand = {
+  name: "mcp",
+  description: "Show the MCP servers and their status, or reconnect, enable, or disable a server",
+  input: { hint: "[reconnect|enable|disable [<server>|all]]" },
+};
+
+/** The time that the status read after a `/mcp` command can take. */
+const MCP_STATUS_TIMEOUT_MS = 5_000;
+
+/** The time that one reconnect, enable, or disable can take. */
+const MCP_ACTION_TIMEOUT_MS = 30_000;
+
+/** A `/mcp` prompt that gets a replacement for its Claude Code text. `all` is
+ *  true for `all` and for a reconnect without a server name, as in Claude
+ *  Code. `server` is undefined for an enable or a disable without a name. */
+export type McpCommand =
+  | { action: "status" }
+  | { action: "reconnect" | "enable" | "disable"; all: boolean; server?: string };
+
+/** Parse a prompt that is exactly `/mcp`, or `/mcp reconnect`, `/mcp enable`,
+ *  or `/mcp disable` with an optional server name or `all`. Any other `/mcp`
+ *  argument gives null, and the prompt gets no replacement. */
+export function parseMcpCommand(text: string): McpCommand | null {
+  const words = text.trim().split(/\s+/);
+  if (words[0] !== "/mcp") return null;
+  if (words.length === 1) return { action: "status" };
+  const action = words[1]?.toLowerCase();
+  if (action !== "reconnect" && action !== "enable" && action !== "disable") return null;
+  const server = words.slice(2).join(" ");
+  if (server === "all" || (server === "" && action === "reconnect")) {
+    return { action, all: true };
+  }
+  return server === "" ? { action, all: false } : { action, all: false, server };
+}
+
+/** Read the MCP server status for the list after a `/mcp` command. Resolves
+ *  to null when the read fails, takes too long, or `signal` aborts. Then the
+ *  turn keeps the text of Claude Code. */
+export async function readMcpServerStatus(
+  query: Pick<Query, "mcpServerStatus">,
+  signal: AbortSignal,
+  logError: (message: string) => void,
+): Promise<McpServerStatus[] | null> {
+  if (signal.aborted) return null;
+  try {
+    const outcome = await raceTimeoutAndAbort(
+      query.mcpServerStatus(),
+      MCP_STATUS_TIMEOUT_MS,
+      signal,
+    );
+    if (outcome.type === "timeout") {
+      logError("The MCP server status read timed out; keeping the Claude Code text of /mcp");
+    }
+    return outcome.type === "done" ? outcome.value : null;
+  } catch (error) {
+    if (!signal.aborted) {
+      logError(`The MCP server status read failed; keeping the Claude Code text of /mcp: ${error}`);
+    }
+    return null;
+  }
+}
+
+/** The known statuses in the order of the groups and of the summary counts.
+ *  A disabled server is not a group. It is on one line at the end. */
+const GROUP_ORDER: McpServerStatus["status"][] = ["failed", "needs-auth", "pending", "connected"];
+
+const GROUP_TITLES: Partial<Record<McpServerStatus["status"], string>> = {
+  failed: "Failed",
+  "needs-auth": "Needs authentication",
+  pending: "Connecting",
+  connected: "Connected",
+};
+
+const SUMMARY_LABELS: Record<McpServerStatus["status"], string> = {
+  connected: "connected",
+  failed: "failed",
+  "needs-auth": "need authentication",
+  pending: "connecting",
+  disabled: "disabled",
+};
+
+const KNOWN_STATUSES: string[] = [...GROUP_ORDER, "disabled"];
+
+const MAX_ERROR_LENGTH = 160;
+
+/** The longest segment that can be a wrapper. A longer segment is content. */
+const MAX_WRAPPER_LENGTH = 60;
+
+/** True for a server that a `/mcp reconnect` without a name must retry. */
+function needsReconnect(status: McpServerStatus): boolean {
+  return (
+    status.status === "failed" || status.status === "pending" || status.status === "needs-auth"
+  );
+}
+
+/** The text as a Markdown code span. The fence is longer than the longest
+ *  backtick run in the text, so the span shows the text unchanged. The user
+ *  can copy a server name from it into `/mcp reconnect`. */
+function codeSpan(text: string): string {
+  const longestRun = Math.max(0, ...(text.match(/`+/g) ?? []).map((run) => run.length));
+  const fence = "`".repeat(longestRun + 1);
+  // CommonMark strips one space from each end of a span, so a pad keeps the text unchanged.
+  const pad = text.startsWith("`") || text.endsWith("`") || /^ .*[^ ].* $/.test(text) ? " " : "";
+  return `${fence}${pad}${text}${pad}${fence}`;
+}
+
+function isErrorCode(segment: string): boolean {
+  return /^-?\d+$/.test(segment);
+}
+
+/** True for a segment that only wraps the real error, such as
+ *  `MCP startup failed`, `McpError`, `MCP error -32001`, an error code, or a
+ *  Rust or TypeScript type path. */
+function isWrapperSegment(segment: string): boolean {
+  return (
+    isErrorCode(segment) ||
+    segment.includes("::") ||
+    (segment.length <= MAX_WRAPPER_LENGTH &&
+      !/[.!?]/.test(segment) &&
+      /(failed|error|exception)(\s+-?\d+)?$/i.test(segment))
+  );
+}
+
+/** Cut the text to `MAX_ERROR_LENGTH` code points, so a surrogate pair stays whole. */
+function truncate(text: string): string {
+  const chars = Array.from(text);
+  if (chars.length <= MAX_ERROR_LENGTH) return text;
+  const cut = chars.slice(0, MAX_ERROR_LENGTH - 1).join("");
+  return `${cut.trimEnd()}…`;
+}
+
+/** Make an MCP error short and readable for one list item. The result has
+ *  no leading wrapper segments, at most two sentences, and at most
+ *  `MAX_ERROR_LENGTH` code points. A wrapper before an error code stays, so
+ *  an error code is never alone. The result is empty for an error with only
+ *  whitespace. */
+export function cleanMcpError(error: string): string {
+  const segments = error.replace(/\s+/g, " ").trim().split(": ");
+  let start = 0;
+  while (
+    start < segments.length - 1 &&
+    isWrapperSegment(segments[start]!) &&
+    !segments.slice(start + 1).every(isErrorCode)
+  ) {
+    start++;
+  }
+  const content = segments.slice(start).join(": ");
+  return truncate(
+    content
+      .split(/(?<=[.!?]) /)
+      .slice(0, 2)
+      .join(" "),
+  );
+}
+
+function toolCount(status: McpServerStatus): string | undefined {
+  if (!status.tools) return undefined;
+  return status.tools.length === 1 ? "1 tool" : `${status.tools.length} tools`;
+}
+
+/** The server name as inline code. Claude Code keys the servers by name, so
+ *  two servers have the same name only from different scopes. Then the
+ *  scope tells them apart. */
+function serverName(status: McpServerStatus, duplicates: Set<string>): string {
+  const origin = status.scope ?? status.source;
+  return duplicates.has(status.name) && origin
+    ? `${codeSpan(status.name)} (${escapeMarkdown(origin)})`
+    : codeSpan(status.name);
+}
+
+function serverItem(status: McpServerStatus, duplicates: Set<string>): string {
+  const error = status.error ? cleanMcpError(status.error) : "";
+  const details = [error === "" ? undefined : escapeMarkdown(error), toolCount(status)]
+    .filter((detail) => detail !== undefined)
+    .join("; ");
+  const name = serverName(status, duplicates);
+  return details === "" ? `- ${name}` : `- ${name}: ${details}`;
+}
+
+function summaryLine(statuses: McpServerStatus[]): string {
+  // The counts follow the group order. An unknown status also counts, so the counts add up to the total.
+  const counts = [...GROUP_ORDER, ...unknownStatuses(statuses), "disabled"]
+    .map((state) => ({
+      state,
+      count: statuses.filter((status) => status.status === state).length,
+    }))
+    .filter(({ count }) => count > 0);
+  const parts = counts.map(({ state, count }) =>
+    count === 1 && state === "needs-auth"
+      ? "1 needs authentication"
+      : `${count} ${SUMMARY_LABELS[state as McpServerStatus["status"]] ?? escapeMarkdown(state)}`,
+  );
+  return `**MCP servers:** ${statuses.length} (${parts.join(", ")})`;
+}
+
+/** The statuses that this adapter does not know, in the SDK order. The SDK
+ *  can report a new status before the adapter knows it. */
+function unknownStatuses(statuses: McpServerStatus[]): string[] {
+  return [
+    ...new Set(
+      statuses
+        .map((status) => status.status as string)
+        .filter((state) => !KNOWN_STATUSES.includes(state)),
+    ),
+  ];
+}
+
+/** The group title of a status that the adapter does not know. It starts with a capital letter, as a known title does. */
+function unknownTitle(state: string): string {
+  return escapeMarkdown(state.charAt(0).toUpperCase() + state.slice(1));
+}
+
+/** Markdown for `/mcp`: a summary line, one group of servers for each
+ *  status, and the disabled servers on one line. A list reads better than a
+ *  table in a narrow chat. */
+export function formatMcpStatus(statuses: McpServerStatus[]): string {
+  if (statuses.length === 0) return "No MCP servers are configured.";
+  const blocks: string[] = [];
+  const names = statuses.map((status) => status.name);
+  const duplicates = new Set(names.filter((name, index) => names.indexOf(name) !== index));
+  blocks.push(summaryLine(statuses));
+  const groups: [string, string][] = [
+    ...GROUP_ORDER.map((state): [string, string] => [state, GROUP_TITLES[state]!]),
+    ...unknownStatuses(statuses).map((state): [string, string] => [state, unknownTitle(state)]),
+  ];
+  for (const [state, title] of groups) {
+    const members = statuses.filter((status) => status.status === state);
+    if (members.length === 0) continue;
+    blocks.push(
+      [`**${title}**`, ...members.map((status) => serverItem(status, duplicates))].join("\n"),
+    );
+  }
+  const disabled = statuses.filter((status) => status.status === "disabled");
+  if (disabled.length > 0) {
+    blocks.push(
+      `**Disabled:** ${disabled.map((status) => serverName(status, duplicates)).join(", ")}`,
+    );
+  }
+  if (statuses.some(needsReconnect)) {
+    blocks.push(
+      "Run `/mcp reconnect <server>` to reconnect one server, or `/mcp reconnect` to reconnect every server that is not connected and not disabled.",
+    );
+  }
+  return blocks.join("\n\n");
+}
+
+/** The SDK query methods that `/mcp` uses. */
+export type McpControlQuery = Pick<
+  Query,
+  "mcpServerStatus" | "reconnectMcpServer" | "toggleMcpServer"
+>;
+
+/** The result of {@link runMcpCommand}. `markdown` is null when the turn
+ *  keeps the text of Claude Code. `reconnected` holds the servers that the
+ *  adapter tried to reconnect. */
+export type McpCommandOutcome = { markdown: string | null; reconnected: string[] };
+
+type CallResult = { type: "done" } | { type: "failed"; error: string } | { type: "aborted" };
+
+/** Wait for one control call. The wait stops when `signal` aborts or the
+ *  call takes more than {@link MCP_ACTION_TIMEOUT_MS}. */
+async function awaitCall(call: () => Promise<void>, signal: AbortSignal): Promise<CallResult> {
+  if (signal.aborted) return { type: "aborted" };
+  try {
+    const outcome = await raceTimeoutAndAbort(call(), MCP_ACTION_TIMEOUT_MS, signal);
+    if (outcome.type === "timeout") return { type: "failed", error: "The request timed out." };
+    return outcome.type === "done" ? { type: "done" } : outcome;
+  } catch (error) {
+    return signal.aborted
+      ? { type: "aborted" }
+      : { type: "failed", error: error instanceof Error ? error.message : String(error) };
+  }
+}
+
+const ACTION_DONE = { reconnect: "Reconnected", enable: "Enabled", disable: "Disabled" };
+
+/** The Claude Code sentence that refuses an action in SDK mode. */
+const UNAVAILABLE_SENTENCE = /aren't available in this session/i;
+
+/** A Claude Code sentence that points to a terminal, which an ACP client
+ *  does not have. */
+function isTerminalSentence(sentence: string): boolean {
+  return /in the terminal/i.test(sentence) || sentence.includes("`/mcp reconnect all` here");
+}
+
+function sentences(text: string): string[] {
+  return text
+    .trim()
+    .split(/(?<=[.!?])\s+/)
+    .filter((sentence) => sentence !== "");
+}
+
+/** The servers that the action changes. A named server is always a target,
+ *  so the control API reports its own error. */
+function actionTargets(
+  command: Extract<McpCommand, { all: boolean }>,
+  statuses: McpServerStatus[],
+): string[] {
+  if (!command.all) return command.server === undefined ? [] : [command.server];
+  const names = statuses
+    .filter((status) => {
+      if (command.action === "reconnect") return needsReconnect(status);
+      if (command.action === "enable") return status.status === "disabled";
+      return status.status !== "disabled";
+    })
+    .map((status) => status.name);
+  return [...new Set(names)];
+}
+
+function nothingToDoLine(action: McpCommand["action"]): string {
+  if (action === "enable") return "Every MCP server is already enabled.";
+  if (action === "disable") return "Every MCP server is already disabled.";
+  return "Every MCP server is connected or disabled. There is nothing to reconnect.";
+}
+
+/** Run a `/mcp` command after Claude Code sent `originalOutput`, its text for
+ *  the command. Claude Code refuses a reconnect, an enable, and a disable in
+ *  SDK mode, so the adapter runs them through the SDK control API. The result
+ *  of each server goes above the server list. An error of one server does
+ *  not stop the others. When the first status read fails or `signal`
+ *  aborts, the turn keeps the text of Claude Code. */
+export async function runMcpCommand(
+  query: McpControlQuery,
+  command: McpCommand,
+  originalOutput: string,
+  signal: AbortSignal,
+  logError: (message: string) => void,
+): Promise<McpCommandOutcome> {
+  const reconnected: string[] = [];
+  const keep: McpCommandOutcome = { markdown: null, reconnected };
+  if (command.action === "status") {
+    // The list replaces the Claude Code summary line.
+    const statuses = await readMcpServerStatus(query, signal, logError);
+    return { markdown: statuses ? formatMcpStatus(statuses) : null, reconnected };
+  }
+  const before = await readMcpServerStatus(query, signal, logError);
+  if (!before) return keep;
+
+  const cliSentences = sentences(originalOutput).filter(
+    (sentence) => !isTerminalSentence(sentence),
+  );
+  const cliNamesUnknown = cliSentences.some((sentence) => /no MCP server named/i.test(sentence));
+  const results: string[] = [];
+  if (!command.all && command.server === undefined) {
+    results.push(`Name a server or \`all\`, for example \`/mcp ${command.action} <server>\`.`);
+  }
+  const known = new Set(before.map((status) => status.name));
+  const targets = actionTargets(command, before);
+  if (command.all && targets.length === 0) results.push(nothingToDoLine(command.action));
+  for (const server of targets) {
+    if (!known.has(server)) {
+      // Claude Code checks the name first. Its sentence then stays.
+      if (!cliNamesUnknown) results.push(`There's no MCP server named ${codeSpan(server)}.`);
+      continue;
+    }
+    if (command.action === "reconnect") reconnected.push(server);
+    const call =
+      command.action === "reconnect"
+        ? () => query.reconnectMcpServer(server)
+        : () => query.toggleMcpServer(server, command.action === "enable");
+    const result = await awaitCall(call, signal);
+    if (result.type === "aborted") return keep;
+    if (result.type === "done") {
+      results.push(`- ${ACTION_DONE[command.action]} ${codeSpan(server)}`);
+    } else {
+      const error = cleanMcpError(result.error);
+      const failure = `- Couldn't ${command.action} ${codeSpan(server)}`;
+      results.push(error === "" ? failure : `${failure}: ${escapeMarkdown(error)}`);
+    }
+  }
+
+  const blocks: string[] = [];
+  const kept = cliSentences.filter((sentence) => !UNAVAILABLE_SENTENCE.test(sentence));
+  if (kept.length > 0) blocks.push(kept.join(" "));
+  if (results.length > 0) blocks.push(results.join("\n"));
+  const after = await readMcpServerStatus(query, signal, logError);
+  if (signal.aborted) return keep;
+  if (after) blocks.push(formatMcpStatus(after));
+  return { markdown: blocks.join("\n\n"), reconnected };
+}
--- a/src/native-subagents.ts
+++ b/src/native-subagents.ts
@@ -324,10 +324,13 @@ export class NativeSubagentRuntime {
  /**
   * The route of the work that a child tool call started, for example an async
   * task. The route sends each update to the child generation that owned the
-   * tool call when the work started, and drops the update after that child
-   * finished. `undefined` means that the root session owns the tool call.
-   * `eagerSessionId` is the session where a permission request created the
-   * tool call before the stream routed it.
+   * tool call when the work started. An async task can outlive that child: a
+   * subagent can start a background command and end its turn. So the route
+   * still sends `async_task_spawned`, `async_task_progress` and
+   * `async_task_state_update` to the child generation after it finished. The route drops every other update
+   * after the child finished. `undefined` means that the root session owns the
+   * tool call. `eagerSessionId` is the session where a permission request
+   * created the tool call before the stream routed it.
   */
  routeOfToolCall(
    toolCallId: string,
@@ -337,7 +340,13 @@ export class NativeSubagentRuntime {
    const owner =
      this.childByToolCall.get(toolCallId) ??
      (eagerSessionId ? this.childOfSession(eagerSessionId) : undefined);
-    return owner && ((notification) => this.toChild(owner, notification, undefined));
+    return (
+      owner &&
+      ((notification) =>
+        isLateAsyncTaskUpdate(notification)
+          ? { ...notification, sessionId: owner.sessionId }
+          : this.toChild(owner, notification, undefined))
+    );
  }

  private rememberToolCallOwner(toolCallId: string, child: NativeSubagent): void {
@@ -581,6 +590,20 @@ export function isNativeSubagentControlTool(toolName: unknown): boolean {
  return toolName === "Agent" || toolName === "Task";
 }

+/**
+ * An async task update that may reach a child generation after it finished.
+ * The spawn is one of them: a held task can get its tool call id, and so its
+ * spawn, after the child finished.
+ */
+function isLateAsyncTaskUpdate(notification: AcpSessionNotification): boolean {
+  const kind = notification.update.sessionUpdate;
+  return (
+    kind === "async_task_spawned" ||
+    kind === "async_task_progress" ||
+    kind === "async_task_state_update"
+  );
+}
+
 function isFailedToolCallUpdate(update: AcpSessionNotification["update"]): boolean {
  return (
    (update.sessionUpdate === "tool_call" || update.sessionUpdate === "tool_call_update") &&
--- a/src/permissions/presentation.ts
+++ b/src/permissions/presentation.ts
@@ -3,13 +3,26 @@ import { AIR_PERMISSION_KEY, withAirMeta } from "../air-extension.js";
 import { ClientCapabilities } from "../tool-calls/client-capabilities.js";
 import { AcpToolCallRenderer } from "../tool-calls/renderer.js";

+/**
+ * A permission request as the agent builds it. For a v2 client it also
+ * carries the heading and the explanation of the prompt, which ACP v2 sends as
+ * the request's `title` and `description`. v1 has no field for them; AIR gets
+ * them in `_meta`.
+ */
+export type AcpPermissionRequest = RequestPermissionRequest & {
+  /** The heading of the prompt. It is not the title of the tool call. */
+  title?: string;
+  /** Why the permission is asked. */
+  description?: string;
+};
+
 export interface ClaudePermissionPresentationInput {
  toolName: string;
  input: Record<string, unknown>;
  toolUseID: string;
  cwd?: string;
  capabilities?: ClientCapabilities;
-  /** The exact patch of the change to approve, for a negotiated `diffPatch` client. */
+  /** The exact patch of the change to approve, for a negotiated `diffPatch` client or a v2 client. */
  previewContent?: ToolCallContent[];
  blockedPath?: string;
  title?: string;
@@ -50,10 +63,13 @@ function compactText(value: unknown): string | undefined {
 * adapter emits the `tool_call` before the request, so the client already
 * holds the rest. The request adds only what it shows new: the exact preview
 * patch, and the blocked path when the tool call has no such location.
+ *
+ * The heading and the explanation of the prompt go to AIR in `_meta`, and to a
+ * v2 client as `title` and `description`.
 */
 export function buildClaudePermissionPresentation(
  value: ClaudePermissionPresentationInput,
-): Pick<RequestPermissionRequest, "toolCall" | "_meta"> {
+): Pick<AcpPermissionRequest, "toolCall" | "_meta" | "title" | "description"> {
  const capabilities = value.capabilities ?? new ClientCapabilities();
  const renderer = new AcpToolCallRenderer(capabilities);
  const toolUse = { id: value.toolUseID, name: value.toolName, input: value.input };
@@ -116,5 +132,6 @@ export function buildClaudePermissionPresentation(
          }),
        }
      : {}),
+    ...(capabilities.v2 ? { title, ...(description ? { description } : {}) } : {}),
  };
 }
--- a/src/resumed-session.ts
+++ b/src/resumed-session.ts
@@ -68,31 +68,46 @@ export async function readResumedSession(
  }
 }

+/** What a resume restores from the end of the local transcript. */
+export type ResumedTail = {
+  model?: string;
+  /** The last permission mode of the main thread. See {@link TailScan}. */
+  permissionMode?: string;
+};
+
 /**
- * Read the resume model of a session from the end of its local transcript.
+ * Read the resume model and the permission mode of a session from the end
+ * of its local transcript.
 *
- * A resume needs only the model, not the messages. The transcript file is
- * read backwards until the last real assistant record of the main thread, so
- * the cost does not grow with the length of the session. A session without a
- * local transcript file falls back to {@link readResumedSession}.
+ * A resume needs only these two values, not the messages. The transcript file
+ * is read backwards until both are known, so the cost does not grow with the
+ * length of the session. A session without a local transcript file falls back
+ * to {@link readResumedSession} for the model.
+ *
+ * A caller that already has the model passes `withModel: false`. The read then
+ * looks for the permission mode only and has no fallback.
 */
-export async function readResumedModel(
+export async function readResumedTail(
  sessionId: string,
  logger?: ResumeLogger,
-): Promise<string | undefined> {
+  withModel = true,
+): Promise<ResumedTail> {
  const timing = new SessionTiming(logger, "models", sessionId);
  try {
    const filePath = await findTranscript(sessionId);
    if (filePath) {
-      const model = await lastAssistantModel(filePath);
-      timing.phase("read-transcript-tail", ` model=${model ?? "unknown"}`);
-      return model;
+      const tail = await lastTailRecords(filePath, withModel);
+      timing.phase(
+        "read-transcript-tail",
+        ` model=${tail.model ?? "unknown"} permissionMode=${tail.permissionMode ?? "unknown"}`,
+      );
+      return tail;
    }
  } catch (error) {
    timing.phase("read-transcript-tail", " outcome=error");
    logger?.error(`Failed to read the transcript tail of resumed session ${sessionId}:`, error);
  }
-  return (await readResumedSession(sessionId, logger)).model;
+  return withModel ? { model: (await readResumedSession(sessionId, logger)).model } : {};
 }

 /** The local transcript of a session in any project directory, as the SDK looks it up. */
@@ -116,9 +131,11 @@ export async function findTranscript(sessionId: string): Promise<string | undefi
  return undefined;
 }

-/** The model of the last real assistant record of the main thread in a JSONL transcript. */
-async function lastAssistantModel(filePath: string): Promise<string | undefined> {
+/** The model of the last real assistant record and the last permission mode
+ * of the main thread in a JSONL transcript. */
+async function lastTailRecords(filePath: string, withModel: boolean): Promise<ResumedTail> {
  const handle = await open(filePath, "r");
+  const scan = new TailScan(withModel);
  try {
    let end = (await handle.stat()).size;
    // The bytes of the line whose start is not read yet, in file order.
@@ -128,31 +145,99 @@ async function lastAssistantModel(filePath: string): Promise<string | undefined>
      let chunk = Buffer.alloc(end - start);
      await handle.read(chunk, 0, chunk.length, start);
      for (let at = chunk.lastIndexOf(0x0a); at >= 0; at = chunk.lastIndexOf(0x0a)) {
-        const model = assistantModelOfLine(Buffer.concat([chunk.subarray(at + 1), ...pending]));
-        if (model) return model;
+        if (scan.visit(Buffer.concat([chunk.subarray(at + 1), ...pending]))) return scan.tail;
        pending = [];
        chunk = chunk.subarray(0, at);
      }
      pending.unshift(chunk);
      end = start;
    }
-    return assistantModelOfLine(Buffer.concat(pending));
+    scan.visit(Buffer.concat(pending));
+    return scan.tail;
  } finally {
    await handle.close();
  }
 }

-function assistantModelOfLine(line: Buffer): string | undefined {
-  // Most lines are not assistant records. The check skips their JSON parse.
-  if (line.indexOf('"assistant"') < 0) return undefined;
+type TranscriptRecord = {
+  type?: unknown;
+  isSidechain?: unknown;
+  message?: { model?: unknown };
+  permissionMode?: unknown;
+  origin?: { kind?: unknown };
+  attachment?: { type?: unknown };
+};
+
+/**
+ * Reads the lines of a transcript from the end and keeps what a resume needs.
+ *
+ * Claude Code records the permission mode on each prompt record of type `user`.
+ * The `permission-mode` records of the CLI metadata block are not used: they
+ * can disagree with the prompts, and the SDK does not write them.
+ * The SDK writes no record when it leaves plan mode through ExitPlanMode.
+ * It writes a `plan_mode_exit` attachment only, without the new mode. Thus a
+ * `plan` mode before a later plan exit is not the current mode, and the scan
+ * gives no mode.
+ *
+ * The mode search stops at the first mode record or at the last human prompt.
+ * Each human prompt of a current Claude Code has the mode, so a prompt without
+ * it means that the transcript does not record modes. A compaction does not
+ * stop the search: the mode of the prompt before it is still current.
+ */
+class TailScan {
+  readonly tail: ResumedTail = {};
+  private modeDone = false;
+  private planExited = false;
+
+  constructor(private readonly withModel: boolean) {}
+
+  /** Visit the previous line. Return true when the scan has all it needs. */
+  visit(line: Buffer): boolean {
+    let parsed: TranscriptRecord | null | undefined;
+    // Most lines have no marker of interest. The check skips their JSON parse.
+    const record = (marker: string): TranscriptRecord | undefined => {
+      if (line.indexOf(marker) < 0) return undefined;
+      if (parsed === undefined) parsed = parseMainThreadRecord(line);
+      return parsed ?? undefined;
+    };
+    if (this.withModel && this.tail.model === undefined) {
+      const entry = record('"assistant"');
+      if (entry?.type === "assistant") this.tail.model = concreteModel(entry.message?.model);
+    }
+    if (!this.modeDone) this.visitForMode(record);
+    return (!this.withModel || this.tail.model !== undefined) && this.modeDone;
+  }
+
+  private visitForMode(record: (marker: string) => TranscriptRecord | undefined): void {
+    const modeEntry = record('"permissionMode"');
+    if (
+      modeEntry?.type === "user" &&
+      typeof modeEntry.permissionMode === "string" &&
+      modeEntry.permissionMode.trim() !== ""
+    ) {
+      const mode = modeEntry.permissionMode.trim();
+      this.modeDone = true;
+      if (!(this.planExited && mode === "plan")) this.tail.permissionMode = mode;
+      return;
+    }
+    if (record('"plan_mode_exit"')?.attachment?.type === "plan_mode_exit") {
+      this.planExited = true;
+      return;
+    }
+    const human = record('"human"');
+    if (human?.type === "user" && human.origin?.kind === "human") this.modeDone = true;
+  }
+}
+
+/** The parsed record of one line, or null for a subagent record or a bad line. */
+function parseMainThreadRecord(line: Buffer): TranscriptRecord | null {
  let entry: unknown;
  try {
    entry = JSON.parse(line.toString("utf8"));
  } catch {
-    return undefined;
+    return null;
  }
-  if (!entry || typeof entry !== "object") return undefined;
-  const record = entry as { type?: unknown; isSidechain?: unknown; message?: { model?: unknown } };
-  if (record.type !== "assistant" || record.isSidechain === true) return undefined;
-  return concreteModel(record.message?.model);
+  if (!entry || typeof entry !== "object") return null;
+  const record = entry as TranscriptRecord;
+  return record.isSidechain === true ? null : record;
 }
--- a/src/serve.ts
+++ b/src/serve.ts
@@ -0,0 +1,51 @@
+import { ndJsonStream } from "@agentclientprotocol/sdk";
+import * as v2 from "@agentclientprotocol/sdk/experimental/v2";
+import { v1AgentApp, type ClaudeAcpAgent, type Logger } from "./acp-agent.js";
+import { nodeToWebReadable, nodeToWebWritable } from "./utils.js";
+import { v2AgentApp } from "./v2/agent.js";
+
+/**
+ * Serves ACP on stdio.
+ *
+ * With `experimentalV2`, the connection goes through {@link acpProtocolRouter}.
+ * Without it, the adapter serves ACP v1 alone and never routes by protocol
+ * version, exactly as before.
+ */
+export function serveAcp(
+  logger: Logger | undefined,
+  options: { experimentalV2: boolean },
+): { closed: Promise<void>; dispose(): Promise<void> } {
+  const output = nodeToWebWritable(process.stdout);
+  const input = nodeToWebReadable(process.stdin);
+  // The router opens the connection of the negotiated version only when it
+  // reads `initialize`, so a client that leaves before then leaves no agent.
+  let agent: ClaudeAcpAgent | undefined;
+  const onAgent = (created: ClaudeAcpAgent) => {
+    agent = created;
+  };
+  const { closed } = options.experimentalV2
+    ? acpProtocolRouter(logger, onAgent).connect(v2.ndJsonStream(output, input))
+    : v1AgentApp(logger, onAgent).connect(ndJsonStream(output, input));
+  return {
+    closed,
+    dispose: async () => {
+      await agent?.dispose();
+    },
+  };
+}
+
+/**
+ * Routes a connection to the protocol version that the client negotiates in
+ * `initialize`: the experimental draft ACP v2 for a client that requests
+ * version 2 or later, and ACP v1 otherwise. `onAgent` receives the agent of
+ * the connection once the router has opened it.
+ */
+export function acpProtocolRouter(
+  logger: Logger | undefined,
+  onAgent: (agent: ClaudeAcpAgent) => void,
+): v2.AgentProtocolRouter {
+  return v2
+    .agentProtocolRouter()
+    .withV1(v1AgentApp(logger, onAgent))
+    .withV2(v2AgentApp(logger, onAgent));
+}
--- a/src/session-config-ids.ts
+++ b/src/session-config-ids.ts
@@ -1,3 +1,4 @@
 /** Shared sentinels and ids for session preferences managed by the adapter. */
 export const DEFAULT_MODEL_ID = "default";
+export const DEFAULT_AGENT_ID = "default";
 export const EFFORT_CONFIG_ID = "effort";
--- a/src/session-effort.ts
+++ b/src/session-effort.ts
@@ -12,6 +12,18 @@ export function toSdkEffortLevel(value: string | undefined): EffortLevel | null
  return value === undefined || value === "default" ? null : (value as EffortLevel);
 }

+// Since CLI 2.1.284 an `effortLevel` that changes the level, sent without an
+// `ultracode` key, turns ultracode off. The CLI's own effort control keeps
+// ultracode on at any level, so carry a settings-requested ultracode along
+// with every effort apply.
+export function effortFlagSettings(
+  value: string | undefined,
+  settings: Settings,
+): { effortLevel: EffortLevel | null; ultracode?: true } {
+  const effortLevel = toSdkEffortLevel(value);
+  return settings.ultracode === true ? { effortLevel, ultracode: true } : { effortLevel };
+}
+
 function canonicalizeModelSettingsKey(value: string): string {
  return value
    .trim()
--- a/src/session-mode.ts
+++ b/src/session-mode.ts
@@ -13,6 +13,7 @@ import type {
  Query,
 } from "@anthropic-ai/claude-agent-sdk";
 import { AIR_KIND_KEY, airOnlyMeta } from "./air-extension.js";
+import { resolvePermissionMode } from "./permissions/modes.js";
 import {
  noticeOrTranscriptUpdate,
  noticeTranscriptText,
@@ -74,6 +75,37 @@ type InitializeSessionModeParams = {
  allowBypass: boolean;
 };

+/**
+ * The permission mode a new Claude query starts in.
+ *
+ * An explicit mode wins. A resume or a load continues in the mode of the last
+ * user record of the transcript. If that mode is unknown or not available now,
+ * for example bypass, the session starts in `defaultMode` of the settings.
+ */
+export function resolveInitialPermissionMode(
+  sources: { explicit?: PermissionMode; resumed?: string; defaultMode?: unknown },
+  logger: { error: (...args: unknown[]) => void },
+  allowBypass: boolean,
+): PermissionMode {
+  if (sources.explicit !== undefined) {
+    return resolvePermissionMode(sources.explicit, logger, allowBypass);
+  }
+  if (sources.resumed !== undefined) {
+    let rejected = false;
+    const mode = resolvePermissionMode(
+      sources.resumed,
+      { error: () => (rejected = true) },
+      allowBypass,
+    );
+    if (!rejected) return mode;
+    logger.error(
+      `Ignoring permission mode "${sources.resumed}" of the resumed transcript: ` +
+        `not available in this session.`,
+    );
+  }
+  return resolvePermissionMode(sources.defaultMode, logger, allowBypass);
+}
+
 /** Owns session-mode policy and the ACP/SDK synchronization it requires. */
 export class SessionModeManager<S extends SessionMode> {
  constructor(private readonly options: SessionModeManagerOptions<S>) {}
--- a/src/session-model.ts
+++ b/src/session-model.ts
@@ -260,6 +260,39 @@ function resolveSettingsModel(
  return resolveModelPreference(models, settingsModel);
 }

+const MODEL_FAMILY_ALIASES = new Set(["opus", "sonnet", "haiku", "fable"]);
+
+/** A model id without the spellings `deniedModels` ignores: provider
+ *  prefixes, dates, version suffixes, `-fast` and context hints. */
+function normalizeDeniedModelId(value: string): string {
+  let id = stripContextHints(value.trim().toLowerCase());
+  const providerPrefix = id.lastIndexOf("anthropic.");
+  if (providerPrefix !== -1) id = id.slice(providerPrefix + "anthropic.".length);
+  return id
+    .replace(/@.*$/, "")
+    .replace(/-v\d+(?::\d+)?$/, "")
+    .replace(/-fast$/, "")
+    .replace(/-\d{8}$/, "");
+}
+
+/**
+ * Whether managed `deniedModels` blocks a model id, following the CLI's rules
+ * closely enough for the picker: a family alias blocks the whole family, and a
+ * model id blocks that version in every spelling plus the later minor versions
+ * it prefixes (`claude-opus-5` also blocks `claude-opus-5-5`). The CLI stays
+ * the enforcer; this only keeps the picker from offering a refused row.
+ */
+export function isDeniedModel(modelId: string, deniedModels: readonly string[]): boolean {
+  const id = normalizeDeniedModelId(modelId);
+  if (!id) return false;
+  return deniedModels.some((entry) => {
+    const denied = normalizeDeniedModelId(entry);
+    if (!denied) return false;
+    if (MODEL_FAMILY_ALIASES.has(denied)) return id === denied || id.includes(`-${denied}`);
+    return id === denied || id.startsWith(`${denied}-`);
+  });
+}
+
 /**
 * Restrict the SDK's model list to the user's `availableModels` allowlist
 * (already merged-and-deduped across settings sources by `SettingsManager`).
@@ -275,11 +308,14 @@ function resolveSettingsModel(
 * - `undefined` is handled by the caller (no allowlist applied).
 * - The Default option is unaffected by `availableModels` — it always remains
 *   available, even when the allowlist is `[]`.
+ * - Managed `deniedModels` wins over the allowlist, so a denied entry is
+ *   dropped even though the CLI would otherwise leave it unmatched.
 */
 export function applyAvailableModelsAllowlist(
  sdkModels: ModelInfo[],
  allowlist: string[],
  settingsModelOverrides?: Record<string, string>,
+  deniedModels: readonly string[] = [],
 ): ModelInfo[] {
  // Default is always preserved per the docs. Synthesize one if the SDK
  // didn't surface it so downstream code (e.g. `getAvailableModels` picking
@@ -310,6 +346,13 @@ export function applyAvailableModelsAllowlist(
    if (seen.has(effective)) continue;

    const sdkMatch = resolveModelPreference(sdkModelsWithoutDefault, trimmed);
+    if (
+      [trimmed, effective, sdkMatch?.resolvedModel].some(
+        (id) => id != null && isDeniedModel(id, deniedModels),
+      )
+    ) {
+      continue;
+    }
    if (sdkMatch) {
      result.push({ ...sdkMatch, value: effective });
    } else {
--- a/src/settings.ts
+++ b/src/settings.ts
@@ -49,6 +49,7 @@ export interface SettingsManagerOptions {
 export class SettingsManager {
  private cwd: string;
  private effective: Settings = {};
+  private managedDeniedModels: string[] = [];
  private watchers: fs.FSWatcher[] = [];
  private onChange?: () => void;
  private logger: { log: (...args: any[]) => void; error: (...args: any[]) => void };
@@ -106,9 +107,14 @@ export class SettingsManager {
    try {
      const resolved = await resolveSettings({ cwd: this.cwd });
      this.effective = filterEscalatingDefaultMode(resolved);
+      // The CLI reads `deniedModels` from managed settings only.
+      this.managedDeniedModels = resolved.sources
+        .filter((entry) => entry.source === "managed")
+        .flatMap((entry) => entry.settings.deniedModels ?? []);
    } catch (error) {
      this.logger.error("Failed to resolve settings:", error);
      this.effective = {};
+      this.managedDeniedModels = [];
    }
  }

@@ -171,6 +177,14 @@ export class SettingsManager {
    return this.effective;
  }

+  /**
+   * `deniedModels` entries from the managed tier, the only tier the CLI
+   * honors them from.
+   */
+  getManagedDeniedModels(): string[] {
+    return this.managedDeniedModels;
+  }
+
  /**
   * Returns the current working directory
   */
--- a/src/tests/acp-agent-settings.test.ts
+++ b/src/tests/acp-agent-settings.test.ts
@@ -154,6 +154,51 @@ describe("ClaudeAcpAgent settings", () => {
    },
  );

+  it("keeps a settings-requested ultracode on when applying effort", async () => {
+    // Since CLI 2.1.284 an effortLevel apply without an ultracode key turns
+    // ultracode off; the CLI's own effort control keeps it on.
+    await fs.promises.writeFile(
+      path.join(tempDir, "settings.json"),
+      JSON.stringify({ ultracode: true }),
+    );
+    const applyFlagSettings = vi.fn();
+    querySpy.mockReturnValue(
+      makeMockQuery({
+        initializationResult: async () => ({
+          models: [
+            {
+              value: "default",
+              displayName: "Default",
+              description: "",
+              supportsEffort: true,
+              supportedEffortLevels: ["low", "medium", "high"],
+            },
+          ],
+        }),
+        applyFlagSettings,
+      }),
+    );
+    const { ClaudeAcpAgent } = await import("../acp-agent.js");
+    const agent = new ClaudeAcpAgent(createMockClient());
+    (agent as any).clientCapabilities = {
+      _meta: { jetbrains: { air: { version: 1, capabilities: ["recommendedValue"] } } },
+    };
+
+    const response = await (agent as any).createSession({
+      cwd: tempDir,
+      mcpServers: [],
+      _meta: { disableBuiltInTools: true },
+    });
+    expect(applyFlagSettings).toHaveBeenLastCalledWith({ effortLevel: "medium", ultracode: true });
+
+    await agent.setSessionConfigOption({
+      sessionId: response.sessionId,
+      configId: "effort",
+      value: "high",
+    });
+    expect(applyFlagSettings).toHaveBeenLastCalledWith({ effortLevel: "high", ultracode: true });
+  });
+
  it("seeds effort from higher-priority programmatic model settings", async () => {
    await fs.promises.writeFile(
      path.join(tempDir, "settings.json"),
@@ -354,6 +399,142 @@ describe("ClaudeAcpAgent settings", () => {
    expect(response.modes.currentModeId).toBe("default");
  });

+  describe("on resume", () => {
+    const sessionId = "resumed-mode-session";
+
+    async function setup(records: unknown[]) {
+      await fs.promises.writeFile(
+        path.join(tempDir, "settings.json"),
+        JSON.stringify({ permissions: { defaultMode: "plan" } }),
+      );
+      const projectDir = path.join(tempDir, "project");
+      await fs.promises.mkdir(projectDir, { recursive: true });
+      const transcriptDir = path.join(tempDir, "projects", "-project");
+      await fs.promises.mkdir(transcriptDir, { recursive: true });
+      await fs.promises.writeFile(
+        path.join(transcriptDir, `${sessionId}.jsonl`),
+        records.map((record) => JSON.stringify(record)).join("\n") + "\n",
+      );
+
+      const { getCapturedOptions } = mockQuery();
+      const { ClaudeAcpAgent } = await import("../acp-agent.js");
+      const agent: ClaudeAcpAgentType = new ClaudeAcpAgent(createMockClient());
+      (agent as any).logger = { log: () => {}, error: () => {} };
+      return { agent, projectDir, getCapturedOptions };
+    }
+
+    async function resume(records: unknown[], meta: object = {}) {
+      const { agent, projectDir, getCapturedOptions } = await setup(records);
+      const response = await (agent as any).createSession(
+        { cwd: projectDir, mcpServers: [], _meta: { disableBuiltInTools: true, ...meta } },
+        { resume: sessionId },
+      );
+      return { permissionMode: getCapturedOptions().permissionMode, response };
+    }
+
+    let previousUuid: string | null = null;
+    const user = (permissionMode?: string) => {
+      const uuid = crypto.randomUUID();
+      const record = {
+        type: "user",
+        uuid,
+        parentUuid: previousUuid,
+        sessionId,
+        timestamp: new Date().toISOString(),
+        isSidechain: false,
+        origin: { kind: "human" },
+        message: { role: "user", content: "hello" },
+        ...(permissionMode ? { permissionMode } : {}),
+      };
+      previousUuid = uuid;
+      return record;
+    };
+
+    it("continues in the last permission mode of the transcript", async () => {
+      const { permissionMode, response } = await resume([user("plan"), user("acceptEdits")]);
+
+      expect(permissionMode).toBe("acceptEdits");
+      expect(response.modes.currentModeId).toBe("acceptEdits");
+    });
+
+    it("uses permissions.defaultMode when the transcript has no mode", async () => {
+      const { permissionMode, response } = await resume([user()]);
+
+      expect(permissionMode).toBe("plan");
+      expect(response.modes.currentModeId).toBe("plan");
+    });
+
+    it("uses permissions.defaultMode when bypass is not available now", async () => {
+      const { permissionMode, response } = await resume([user("bypassPermissions")], {
+        claudeCode: { options: { allowDangerouslySkipPermissions: false } },
+      });
+
+      expect(permissionMode).toBe("plan");
+      expect(response.modes.currentModeId).toBe("plan");
+    });
+
+    it("continues in the last permission mode on session/load", async () => {
+      const { agent, projectDir, getCapturedOptions } = await setup([
+        user("plan"),
+        user("acceptEdits"),
+      ]);
+
+      const response = await agent.loadSession({
+        sessionId,
+        cwd: projectDir,
+        mcpServers: [],
+        _meta: { disableBuiltInTools: true },
+      });
+
+      expect(getCapturedOptions().permissionMode).toBe("acceptEdits");
+      expect(response.modes?.currentModeId).toBe("acceptEdits");
+    });
+
+    it("keeps the live mode when it recreates the session", async () => {
+      const { agent, projectDir, getCapturedOptions } = await setup([user("acceptEdits")]);
+      const params = { sessionId, cwd: projectDir, _meta: { disableBuiltInTools: true } };
+      await agent.resumeSession({ ...params, mcpServers: [] });
+      await agent.setSessionMode({ sessionId, modeId: "default" });
+
+      // Other MCP servers change the fingerprint, so the agent recreates the query.
+      const response = await agent.resumeSession({
+        ...params,
+        mcpServers: [{ name: "other", command: "true", args: [], env: [] }],
+      });
+
+      expect(getCapturedOptions().permissionMode).toBe("default");
+      expect(response.modes?.currentModeId).toBe("default");
+    });
+
+    it("keeps the live mode when a sign-out respawn starts a fresh conversation", async () => {
+      const { agent, projectDir, getCapturedOptions } = await setup([user("acceptEdits")]);
+      await agent.resumeSession({
+        sessionId,
+        cwd: projectDir,
+        mcpServers: [],
+        _meta: { disableBuiltInTools: true },
+      });
+      await agent.setSessionMode({ sessionId, modeId: "default" });
+      const { RequestError } = await import("@agentclientprotocol/sdk");
+      const createSession = (agent as any).createSession.bind(agent);
+      const creations: object[] = [];
+      (agent as any).createSession = async (params: object, options: { resume?: string }) => {
+        creations.push(options);
+        // The CLI never wrote the conversation, so the resume fails.
+        if (options.resume) throw RequestError.resourceNotFound(sessionId);
+        return createSession(params, options);
+      };
+
+      await (agent as any).recreateSignedOutQuery(sessionId, (agent as any).sessions[sessionId]);
+
+      expect(creations).toEqual([
+        { resume: sessionId, permissionMode: "default" },
+        { reuseSessionId: sessionId, permissionMode: "default" },
+      ]);
+      expect(getCapturedOptions().permissionMode).toBe("default");
+    });
+  });
+
  it("falls back to 'default' when permissions.defaultMode is invalid", async () => {
    await fs.promises.writeFile(
      path.join(tempDir, "settings.json"),
--- a/src/tests/acp-agent.test.ts
+++ b/src/tests/acp-agent.test.ts
--- a/src/tests/acp-scenarios-compare.test.ts
+++ b/src/tests/acp-scenarios-compare.test.ts
@@ -60,4 +60,39 @@ describe("compareWithBaseline", () => {
      expect.stringMatching(/^origin\/main did not send /u),
    ]);
  });
+
+  describe("available_commands_update", () => {
+    const commands = (...names: string[]) =>
+      update({
+        sessionUpdate: "available_commands_update",
+        availableCommands: names.map((name) => ({ name, description: name })),
+      });
+
+    it("accepts the mcp command of the adapter", () => {
+      expect(compareWithBaseline([commands("compact")], [commands("compact", "mcp")])).toEqual([]);
+      expect(compareWithBaseline([commands()], [commands("mcp")])).toEqual([]);
+    });
+
+    it("reports any other extra command", () => {
+      expect(compareWithBaseline([commands()], [commands("mcp", "other")])).toContainEqual(
+        expect.stringMatching(/but the adapter sent .*"name":"other"/u),
+      );
+    });
+
+    it("reports a dropped command", () => {
+      expect(compareWithBaseline([commands("compact")], [commands("mcp")])).toContainEqual(
+        expect.stringMatching(/^origin\/main sent .*"name":"compact"/u),
+      );
+    });
+
+    it("reports a changed mcp command that origin/main listed", () => {
+      const changed = update({
+        sessionUpdate: "available_commands_update",
+        availableCommands: [{ name: "mcp", description: "other" }],
+      });
+      expect(compareWithBaseline([commands("mcp")], [changed])).toContainEqual(
+        expect.stringMatching(/but the adapter sent .*"description":"other"/u),
+      );
+    });
+  });
 });
--- a/src/tests/acp-scenarios-v2.test.ts
+++ b/src/tests/acp-scenarios-v2.test.ts
@@ -0,0 +1,171 @@
+/**
+ * Every scenario of `acp-scenarios/scenarios.ts` on the experimental ACP v2
+ * surface: through the protocol router, with the SDK's v2 client.
+ *
+ * - Status: each scenario passes, every prompt turn ending with a stop reason,
+ *   unless {@link V2_STOPS} names why it stops. Every scenario passes today;
+ *   a scenario that the v2 surface cannot run yet goes in the table.
+ * - Schema: every message the agent sends, also in a scenario that stops, is
+ *   valid against the draft v2 schema of the SDK.
+ * - Tool calls: the first report of each tool call has a title. v2 has no
+ *   `tool_call`, so a report of a tool call that the client has not seen
+ *   creates it, where v1 drops it.
+ * - Golden files: `acp-scenarios/__snapshots__/v2/<scenario>.jsonl` for each
+ *   passing scenario. Run `npx vitest run src/tests/acp-scenarios-v2.test.ts -u`
+ *   to update them.
+ */
+import { afterAll, beforeAll, describe, expect, it, vi } from "vitest";
+import * as fs from "node:fs";
+import * as os from "node:os";
+import * as path from "node:path";
+import { fileURLToPath } from "node:url";
+import type { ClaudeAcpAgent } from "../acp-agent.js";
+import {
+  resetIds,
+  runScenarioV2,
+  type ScenarioRunV2,
+  type WireRecorded,
+} from "./acp-scenarios/harness.js";
+import { SCENARIOS } from "./acp-scenarios/scenarios.js";
+import { canonical } from "./acp-scenarios/compare.js";
+import { validateV2Message } from "./acp-scenarios/schema.js";
+
+vi.mock("@anthropic-ai/claude-agent-sdk", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@anthropic-ai/claude-agent-sdk")>();
+  const harness = await import("./acp-scenarios/harness.js");
+  return {
+    ...actual,
+    query: harness.mockedQuery,
+    getSessionMessages: harness.mockedSessionMessages,
+  };
+});
+
+// The recordings replace only the ids that the run generated, so the harness
+// learns each id that `randomUUID` returns.
+vi.mock("node:crypto", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("node:crypto")>();
+  const harness = await import("./acp-scenarios/harness.js");
+  return {
+    ...actual,
+    randomUUID: (...args: Parameters<typeof actual.randomUUID>) => {
+      const id = actual.randomUUID(...args);
+      harness.noteGeneratedId(id);
+      return id;
+    },
+  };
+});
+
+const here = path.dirname(fileURLToPath(import.meta.url));
+
+const PASSES = "passes";
+
+/**
+ * The scenarios that stop on the v2 surface, each with the reason, which names
+ * the step of `docs/acp-v2.md` that removes it. Every other scenario passes.
+ */
+const V2_STOPS: Record<string, string> = {};
+
+const statusOf = (scenario: string) => V2_STOPS[scenario] ?? PASSES;
+
+const runs = new Map<string, ScenarioRunV2>();
+let configDir: string;
+
+beforeAll(async () => {
+  // A run must not depend on the machine: no remote login, no Claude CLI, no
+  // user settings, and the bypass mode also for root.
+  for (const name of ["SSH_CONNECTION", "SSH_CLIENT", "SSH_TTY", "NO_BROWSER"]) {
+    vi.stubEnv(name, "");
+  }
+  vi.stubEnv("CLAUDE_CODE_REMOTE", "");
+  vi.stubEnv("ANTHROPIC_MODEL", "");
+  vi.stubEnv("IS_SANDBOX", "1");
+  vi.stubEnv("CLAUDE_CODE_EXECUTABLE", "/usr/bin/false");
+  configDir = fs.mkdtempSync(path.join(os.tmpdir(), "acp-scenario-config-"));
+  vi.stubEnv("CLAUDE_CONFIG_DIR", configDir);
+  const { acpProtocolRouter } = await import("../serve.js");
+  for (const scenario of SCENARIOS) {
+    resetIds();
+    const agents: ClaudeAcpAgent[] = [];
+    const quiet = { log: () => {}, error: () => {} };
+    runs.set(
+      scenario.name,
+      await runScenarioV2(
+        (stream) => acpProtocolRouter(quiet, (agent) => agents.push(agent)).connect(stream),
+        scenario,
+      ),
+    );
+    await Promise.all(agents.map((agent) => agent.dispose()));
+  }
+}, 120_000);
+
+afterAll(() => {
+  vi.unstubAllEnvs();
+  fs.rmSync(configDir, { recursive: true, force: true });
+});
+
+function run(scenario: string): ScenarioRunV2 {
+  const recorded = runs.get(scenario);
+  if (!recorded) throw new Error(`no v2 run of ${scenario}`);
+  return recorded;
+}
+
+function toJsonLines(recorded: WireRecorded[]): string {
+  return recorded.map((record) => `${canonical(record)}\n`).join("");
+}
+
+describe("ACP v2 scenarios", () => {
+  it("pass, or stop as the table says", () => {
+    const table = (status: (scenario: string) => string) =>
+      Object.fromEntries(SCENARIOS.map((scenario) => [scenario.name, status(scenario.name)]));
+    expect(table((scenario) => run(scenario).status)).toEqual(table(statusOf));
+  });
+
+  describe("schema check", () => {
+    const chunk = (update: Record<string, unknown>): WireRecorded => ({
+      kind: "notification",
+      method: "session/update",
+      payload: { sessionId: "s", update: { sessionUpdate: "agent_message_chunk", ...update } },
+    });
+
+    it("rejects a message that breaks the v2 schema", () => {
+      const content = { type: "text", text: "hi" };
+      expect(validateV2Message(chunk({ messageId: "m", content }))).toEqual([]);
+      // v2 requires the id of the message a chunk belongs to.
+      expect(validateV2Message(chunk({ content }))).not.toEqual([]);
+    });
+
+    it.each(SCENARIOS.map((scenario) => scenario.name))("%s", (scenario) => {
+      expect(run(scenario).raw.flatMap((message) => validateV2Message(message))).toEqual([]);
+    });
+  });
+
+  describe("tool calls are reported with a title first", () => {
+    it.each(SCENARIOS.map((scenario) => scenario.name))("%s", (scenario) => {
+      const reported = new Set<string>();
+      const untitled: string[] = [];
+      for (const message of run(scenario).raw) {
+        if (message.kind !== "notification" || message.method !== "session/update") continue;
+        const { sessionId, update } = message.payload as {
+          sessionId: string;
+          update: { sessionUpdate: string; toolCallId?: string; title?: unknown };
+        };
+        if (update.sessionUpdate !== "tool_call_update") continue;
+        const key = `${sessionId} ${update.toolCallId}`;
+        if (!reported.has(key) && typeof update.title !== "string") untitled.push(key);
+        reported.add(key);
+      }
+      expect(untitled).toEqual([]);
+    });
+  });
+
+  describe("v2 golden files", () => {
+    const passing = SCENARIOS.map((scenario) => scenario.name).filter(
+      (scenario) => statusOf(scenario) === PASSES,
+    );
+    it.each(passing)("%s", async (scenario) => {
+      await expect(toJsonLines(run(scenario).normalized)).toMatchFileSnapshot(
+        path.join(here, "acp-scenarios", "__snapshots__", "v2", `${scenario}.jsonl`),
+      );
+    });
+  });
+});
--- a/src/tests/acp-scenarios.test.ts
+++ b/src/tests/acp-scenarios.test.ts
@@ -50,6 +50,7 @@ import {
  compareWithBaseline,
 } from "./acp-scenarios/compare.js";
 import { EXTENSION_SESSION_UPDATES, validateRecorded } from "./acp-scenarios/schema.js";
+import { LEGACY_AIR_CUSTOM_ANSWER_KEY } from "../air-extension.js";

 vi.mock("@anthropic-ai/claude-agent-sdk", async (importOriginal) => {
  const actual = await importOriginal<typeof import("@anthropic-ai/claude-agent-sdk")>();
@@ -661,6 +662,7 @@ describe.skipIf(baselineDir)("ACP scenarios", () => {
        (record) => record.kind === "createElicitation",
      )!.payload as Record<string, any>;
      expect(elicitation.requestedSchema.properties.question_0_custom._meta).toEqual({
+        _askUserQuestionCustomAnswer: { questionId: "question_0", isCustomAnswer: true },
        jetbrains: {
          air: { version: 1, customAnswer: { questionId: "question_0", isCustomAnswer: true } },
        },
@@ -689,7 +691,13 @@ describe.skipIf(baselineDir)("ACP scenarios", () => {
      for (const scenario of SCENARIOS) {
        for (const { at, meta } of metaObjects(air(scenario.name))) {
          const duplicates = [
-            ...Object.keys(meta).filter((k) => AIR_ONLY_META_KEYS.has(k) && k !== "jetbrains"),
+            // Released AIR versions read only the legacy custom answer key, so AIR gets both.
+            ...Object.keys(meta).filter(
+              (k) =>
+                AIR_ONLY_META_KEYS.has(k) &&
+                k !== "jetbrains" &&
+                k !== LEGACY_AIR_CUSTOM_ANSWER_KEY,
+            ),
            ...Object.keys((meta.claudeCode as Record<string, unknown> | undefined) ?? {}).filter(
              (k) => AIR_ONLY_CLAUDE_CODE_KEYS.has(k),
            ),
--- a/src/tests/acp-scenarios/snapshots/air/ask-user-question.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/ask-user-question.jsonl
@@ -1,9 +1,9 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"AskUserQuestion"}},"content":[],"kind":"other","name":"AskUserQuestion","sessionUpdate":"tool_call","status":"pending","title":"Asking for your input","toolCallId":"toolu_ask"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"rawInput":{"questions":[{"header":"Database","multiSelect":false,"options":[{"description":"Relational","label":"Postgres","preview":"CREATE TABLE t ();"},{"description":"Key-value","label":"Redis"}],"question":"Which database?"}]},"sessionUpdate":"tool_call_update","toolCallId":"toolu_ask"}}}
-{"kind":"createElicitation","payload":{"message":"Which database?","mode":"form","requestedSchema":{"properties":{"question_0":{"oneOf":[{"_meta":{"_claude/askUserQuestionOption":{"preview":"CREATE TABLE t ();"}},"const":"Postgres","description":"Relational","title":"Postgres"},{"const":"Redis","description":"Key-value","title":"Redis"}],"title":"Database","type":"string"},"question_0_custom":{"_meta":{"jetbrains":{"air":{"customAnswer":{"isCustomAnswer":true,"questionId":"question_0"},"version":1}}},"description":"Type your own answer, or add a note to the option you chose above (optional).","title":"Other","type":"string"}},"type":"object"},"sessionId":"<session>","toolCallId":"toolu_ask"}}
+{"kind":"createElicitation","payload":{"message":"Which database?","mode":"form","requestedSchema":{"properties":{"question_0":{"oneOf":[{"_meta":{"_claude/askUserQuestionOption":{"preview":"CREATE TABLE t ();"}},"const":"Postgres","description":"Relational","title":"Postgres"},{"const":"Redis","description":"Key-value","title":"Redis"}],"title":"Database","type":"string"},"question_0_custom":{"_meta":{"_askUserQuestionCustomAnswer":{"isCustomAnswer":true,"questionId":"question_0"},"jetbrains":{"air":{"customAnswer":{"isCustomAnswer":true,"questionId":"question_0"},"version":1}}},"description":"Type your own answer, or add a note to the option you chose above (optional).","title":"Other","type":"string"}},"type":"object"},"sessionId":"<session>","toolCallId":"toolu_ask"}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"User has answered your questions: \"Which database?\"=\"Postgres\".","type":"text"},"type":"content"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_ask"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"promptResponse","payload":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}
--- a/src/tests/acp-scenarios/snapshots/air/async-task-ends-before-tool-id.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/async-task-ends-before-tool-id.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"workflow_1","canStop":true,"description":"Build assets","name":"Build assets","outputFilePath":"/tmp/tasks/workflow_1.output","sessionUpdate":"async_task_spawned","showInTranscript":true,"taskType":"workflow"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"workflow_1","sessionUpdate":"async_task_state_update","state":"completed","summary":"done"}}}
 {"kind":"promptResponse","payload":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}
--- a/src/tests/acp-scenarios/snapshots/air/async-task-held-until-tool-id.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/async-task-held-until-tool-id.jsonl
@@ -1,5 +1,5 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"monitor_1","canStop":true,"description":"Watch the logs","name":"Watch the logs","sessionUpdate":"async_task_spawned","showInTranscript":true,"taskType":"monitor","toolCallId":"toolu_monitor"}}}
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"monitor_1","sessionUpdate":"async_task_progress","summary":"first line","usage":{"durationMs":5,"toolUses":0,"totalTokens":0}}}}
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"monitor_1","sessionUpdate":"async_task_progress","summary":"second line","usage":{"durationMs":6,"toolUses":0,"totalTokens":0}}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"workflow_3","canStop":true,"description":"Watch the logs","name":"Watch the logs","sessionUpdate":"async_task_spawned","showInTranscript":true,"taskType":"workflow","toolCallId":"toolu_workflow"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"workflow_3","sessionUpdate":"async_task_progress","summary":"first line","usage":{"durationMs":5,"toolUses":0,"totalTokens":0}}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"workflow_3","sessionUpdate":"async_task_progress","summary":"second line","usage":{"durationMs":6,"toolUses":0,"totalTokens":0}}}}
 {"kind":"promptResponse","payload":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}
--- a/src/tests/acp-scenarios/snapshots/air/async-task-released-at-turn-end.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/async-task-released-at-turn-end.jsonl
@@ -1,3 +1,3 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"asyncTaskId":"workflow_2","canStop":true,"description":"Build assets","name":"Build assets","sessionUpdate":"async_task_spawned","showInTranscript":true,"taskType":"workflow"}}}
 {"kind":"promptResponse","payload":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}
--- a/src/tests/acp-scenarios/snapshots/air/bash-background.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/bash-background.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"},"terminal_info":{"terminal_id":"toolu_bg"}},"content":[{"terminalId":"toolu_bg","type":"terminal"}],"kind":"execute","name":"Bash","sessionUpdate":"tool_call","status":"pending","title":"Terminal","toolCallId":"toolu_bg"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"sessionUpdate":"tool_call_update","title":"sleep 100","toolCallId":"toolu_bg"}}}
--- a/src/tests/acp-scenarios/snapshots/air/bash-error.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/bash-error.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"},"terminal_info":{"terminal_id":"toolu_bash"}},"content":[{"terminalId":"toolu_bash","type":"terminal"}],"kind":"execute","name":"Bash","sessionUpdate":"tool_call","status":"pending","title":"Terminal","toolCallId":"toolu_bash"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"sessionUpdate":"tool_call_update","title":"false","toolCallId":"toolu_bash"}}}
--- a/src/tests/acp-scenarios/snapshots/air/bash-foreground.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/bash-foreground.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"},"terminal_info":{"terminal_id":"toolu_bash"}},"content":[{"terminalId":"toolu_bash","type":"terminal"}],"kind":"execute","name":"Bash","sessionUpdate":"tool_call","status":"pending","title":"Terminal","toolCallId":"toolu_bash"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"sessionUpdate":"tool_call_update","title":"ls -la","toolCallId":"toolu_bash"}}}
--- a/src/tests/acp-scenarios/snapshots/air/compaction-failed-legacy.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/compaction-failed-legacy.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"jetbrains":{"air":{"contextCompaction":{"version":1},"version":1}}},"kind":"think","sessionUpdate":"tool_call","status":"in_progress","title":"Compact conversation","toolCallId":"00000000-0000-4000-8000-000000000001"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"jetbrains":{"air":{"contextCompaction":{"error":"Context too small","version":1}}}},"content":[{"content":{"text":"Compaction failed: Context too small","type":"text"},"type":"content"}],"sessionUpdate":"tool_call_update","status":"failed","toolCallId":"00000000-0000-4000-8000-000000000001"}}}
 {"kind":"promptResponse","payload":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}
--- a/src/tests/acp-scenarios/snapshots/air/compaction-legacy.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/compaction-legacy.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"jetbrains":{"air":{"contextCompaction":{"version":1},"version":1}}},"kind":"think","sessionUpdate":"tool_call","status":"in_progress","title":"Compact conversation","toolCallId":"00000000-0000-4000-8000-000000000001"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"sessionUpdate":"tool_call_update","status":"in_progress","toolCallId":"00000000-0000-4000-8000-000000000001"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"jetbrains":{"air":{"contextCompaction":{"durationMs":7,"postTokens":100,"preTokens":1000,"trigger":"automatic","version":1}}}},"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"00000000-0000-4000-8000-000000000001"}}}
--- a/src/tests/acp-scenarios/snapshots/air/compaction-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/compaction-update.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"jetbrains":{"air":{"contextCompaction":{"version":1},"version":1}}},"compactionId":"00000000-0000-4000-8000-000000000001","sessionUpdate":"compaction_update","status":"in_progress"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","content":{"text":"The summary.","type":"text"},"sessionUpdate":"compaction_summary_chunk"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"jetbrains":{"air":{"contextCompaction":{"durationMs":7,"postTokens":100,"preTokens":1000,"trigger":"automatic","version":1},"version":1}}},"compactionId":"00000000-0000-4000-8000-000000000001","sessionUpdate":"compaction_update","status":"completed"}}}
--- a/src/tests/acp-scenarios/snapshots/air/edit-rejected.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/edit-rejected.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"content":[],"kind":"edit","locations":[],"name":"Edit","sessionUpdate":"tool_call","status":"pending","title":"Edit","toolCallId":"toolu_edit"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"locations":[{"path":"<cwd>/src/app.ts"}],"sessionUpdate":"tool_call_update","title":"Edit src/app.ts","toolCallId":"toolu_edit"}}}
--- a/src/tests/acp-scenarios/snapshots/air/edit-with-permission.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/edit-with-permission.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"content":[],"kind":"edit","locations":[],"name":"Edit","sessionUpdate":"tool_call","status":"pending","title":"Edit","toolCallId":"toolu_edit"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"locations":[{"path":"<cwd>/src/app.ts"}],"sessionUpdate":"tool_call_update","title":"Edit src/app.ts","toolCallId":"toolu_edit"}}}
--- a/src/tests/acp-scenarios/snapshots/air/exit-plan-approve.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/exit-plan-approve.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"ExitPlanMode"}},"content":[],"kind":"switch_mode","name":"ExitPlanMode","sessionUpdate":"tool_call","status":"pending","title":"Approve Plan","toolCallId":"toolu_plan"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
--- a/src/tests/acp-scenarios/snapshots/air/exit-plan-reject.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/exit-plan-reject.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"ExitPlanMode"}},"content":[],"kind":"switch_mode","name":"ExitPlanMode","sessionUpdate":"tool_call","status":"pending","title":"Approve Plan","toolCallId":"toolu_plan"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
--- a/src/tests/acp-scenarios/snapshots/air/goal.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/goal.jsonl
@@ -1,3 +1,3 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"jetbrains":{"air":{"goal":{"controlMethod":"_session/goal","objective":"Ship the feature","status":"active"},"version":1}}},"sessionUpdate":"session_info_update"}}}
 {"kind":"promptResponse","payload":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}
--- a/src/tests/acp-scenarios/snapshots/air/grep-and-glob.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/grep-and-glob.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Grep"}},"content":[],"kind":"search","name":"Grep","sessionUpdate":"tool_call","status":"pending","title":"grep","toolCallId":"toolu_grep"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"sessionUpdate":"tool_call_update","title":"grep \"value\"","toolCallId":"toolu_grep"}}}
--- a/src/tests/acp-scenarios/snapshots/air/mcp-tool.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/mcp-tool.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"mcp__docs__search"},"is_mcp_tool_call":true},"content":[],"kind":"other","name":"mcp__docs__search","sessionUpdate":"tool_call","status":"pending","title":"mcp__docs__search","toolCallId":"toolu_mcp"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
--- a/src/tests/acp-scenarios/snapshots/air/memory-recall.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/memory-recall.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"memory_recall","toolResponse":{"mode":"select"}}},"kind":"read","locations":[{"path":"/memory/a.md"},{"path":"/memory/b.md"}],"sessionUpdate":"tool_call","status":"completed","title":"Recalled 2 memories","toolCallId":"00000000-0000-4000-8000-000000000001"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"memory_recall","toolResponse":{"mode":"synthesize"}}},"content":[{"content":{"text":"The user prefers tabs.","type":"text"},"type":"content"}],"kind":"read","sessionUpdate":"tool_call","status":"completed","title":"Recalled synthesized memory","toolCallId":"00000000-0000-4000-8000-000000000002"}}}
 {"kind":"promptResponse","payload":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}
--- a/src/tests/acp-scenarios/snapshots/air/network-permission.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/network-permission.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"SandboxNetworkAccess"}},"content":[],"kind":"other","name":"SandboxNetworkAccess","rawInput":{"host":"example.com"},"sessionUpdate":"tool_call","status":"pending","title":"SandboxNetworkAccess","toolCallId":"toolu_net"}}}
 {"kind":"requestPermission","payload":{"_meta":{"jetbrains":{"air":{"permission":{"description":"Reason: Sandbox blocks network","title":"example.com","version":1},"version":1}}},"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","toolCall":{"rawInput":{"host":"example.com"},"title":"example.com","toolCallId":"toolu_net"}}}
 {"kind":"promptResponse","payload":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}
--- a/src/tests/acp-scenarios/snapshots/air/notebook-edit.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/notebook-edit.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"NotebookEdit"}},"content":[],"kind":"edit","locations":[],"name":"NotebookEdit","sessionUpdate":"tool_call","status":"pending","title":"Edit notebook","toolCallId":"toolu_nb"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"locations":[{"path":"<cwd>/n.ipynb"}],"sessionUpdate":"tool_call_update","title":"Edit cell in n.ipynb","toolCallId":"toolu_nb"}}}
--- a/src/tests/acp-scenarios/snapshots/air/permission-denied.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/permission-denied.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"},"terminal_info":{"terminal_id":"toolu_denied"}},"content":[{"terminalId":"toolu_denied","type":"terminal"}],"kind":"execute","name":"Bash","sessionUpdate":"tool_call","status":"pending","title":"Terminal","toolCallId":"toolu_denied"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
--- a/src/tests/acp-scenarios/snapshots/air/rate-limit-and-origin.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/rate-limit-and-origin.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"content":{"text":"Work","type":"text"},"messageId":"msg_rate","sessionUpdate":"agent_message_chunk"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"content":{"text":"ing.","type":"text"},"messageId":"msg_rate","sessionUpdate":"agent_message_chunk"}}}
--- a/src/tests/acp-scenarios/snapshots/air/read.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/read.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Read"}},"content":[],"kind":"read","locations":[],"name":"Read","sessionUpdate":"tool_call","status":"pending","title":"Read File","toolCallId":"toolu_read"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
--- a/src/tests/acp-scenarios/snapshots/air/session-load-replay.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/session-load-replay.jsonl
@@ -12,4 +12,4 @@
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"content":{"text":"Fixed.","type":"text"},"messageId":"msg_r2","sessionUpdate":"agent_message_chunk"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"sessionUpdate":"subagent_state_update","state":"completed","subagentSessionId":"<session>:replay-subagent:toolu_r_task"}}}
 {"kind":"loadSession","payload":{"configOptions":[{"category":"mode","currentValue":"default","description":"Session permission mode","id":"mode","name":"Mode","options":[{"_meta":{"jetbrains":{"air":{"kind":"standard","version":1}}},"description":"Always ask before making changes","name":"Manual","value":"default"},{"_meta":{"jetbrains":{"air":{"kind":"standard","version":1}}},"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"_meta":{"jetbrains":{"air":{"kind":"plan","version":1}}},"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"_meta":{"jetbrains":{"air":{"kind":"auto_review","version":1}}},"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"_meta":{"jetbrains":{"air":{"kind":"full_access","version":1}}},"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","id":"model","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"modes":{"availableModes":[{"_meta":{"jetbrains":{"air":{"kind":"standard","version":1}}},"description":"Always ask before making changes","id":"default","name":"Manual"},{"_meta":{"jetbrains":{"air":{"kind":"standard","version":1}}},"description":"Automatically accept all file edits","id":"acceptEdits","name":"Accept edits"},{"_meta":{"jetbrains":{"air":{"kind":"plan","version":1}}},"description":"Create a plan before making changes","id":"plan","name":"Plan"},{"_meta":{"jetbrains":{"air":{"kind":"auto_review","version":1}}},"description":"Claude handles permission decisions","id":"auto","name":"Auto"},{"_meta":{"jetbrains":{"air":{"kind":"full_access","version":1}}},"description":"Accepts all permissions","id":"bypassPermissions","name":"Bypass permissions"}],"currentModeId":"default"},"sessionId":"<session>"}}
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
--- a/src/tests/acp-scenarios/snapshots/air/session-setup.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/session-setup.jsonl
@@ -1,3 +1,3 @@
 {"kind":"initialize","payload":{"_meta":{"jetbrains":{"air":{"capabilities":["sessionFailure","agentFileChangeReport","nativeSubagentSessions","asyncTasks","recommendedValue","diffPatch","planFile"],"goal":{"actions":["set","clear"],"controlMethod":"_session/goal","version":1},"version":1}},"steering":{"supported":true}},"agentCapabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"auth":{"logout":{}},"loadSession":true,"mcpCapabilities":{"http":true,"sse":true},"promptCapabilities":{"embeddedContext":true,"image":true},"providers":{},"sessionCapabilities":{"additionalDirectories":{},"close":{},"delete":{},"fork":{},"list":{},"resume":{},"subagents":{}}},"agentInfo":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"authMethods":[],"protocolVersion":1}}
 {"kind":"newSession","payload":{"configOptions":[{"category":"mode","currentValue":"default","description":"Session permission mode","id":"mode","name":"Mode","options":[{"_meta":{"jetbrains":{"air":{"kind":"standard","version":1}}},"description":"Always ask before making changes","name":"Manual","value":"default"},{"_meta":{"jetbrains":{"air":{"kind":"standard","version":1}}},"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"_meta":{"jetbrains":{"air":{"kind":"plan","version":1}}},"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"_meta":{"jetbrains":{"air":{"kind":"auto_review","version":1}}},"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"_meta":{"jetbrains":{"air":{"kind":"full_access","version":1}}},"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","id":"model","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"modes":{"availableModes":[{"_meta":{"jetbrains":{"air":{"kind":"standard","version":1}}},"description":"Always ask before making changes","id":"default","name":"Manual"},{"_meta":{"jetbrains":{"air":{"kind":"standard","version":1}}},"description":"Automatically accept all file edits","id":"acceptEdits","name":"Accept edits"},{"_meta":{"jetbrains":{"air":{"kind":"plan","version":1}}},"description":"Create a plan before making changes","id":"plan","name":"Plan"},{"_meta":{"jetbrains":{"air":{"kind":"auto_review","version":1}}},"description":"Claude handles permission decisions","id":"auto","name":"Auto"},{"_meta":{"jetbrains":{"air":{"kind":"full_access","version":1}}},"description":"Accepts all permissions","id":"bypassPermissions","name":"Bypass permissions"}],"currentModeId":"default"},"sessionId":"<session>"}}
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
--- a/src/tests/acp-scenarios/snapshots/air/skill.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/skill.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Skill"}},"content":[],"kind":"other","name":"Skill","sessionUpdate":"tool_call","status":"pending","title":"Load skill","toolCallId":"toolu_skill"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
--- a/src/tests/acp-scenarios/snapshots/air/subagent-agent-async.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/subagent-agent-async.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent","toolResponse":{"isAsync":true,"status":"async_launched"}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_agent"}}}
--- a/src/tests/acp-scenarios/snapshots/air/subagent-late-child-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/subagent-late-child-update.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"capabilities":{},"name":"Check the logs","prompt":"Check logs","sessionUpdate":"subagent_spawned","subagentSessionId":"agent_late","task":"Check logs"}}}
--- a/src/tests/acp-scenarios/snapshots/air/subagent-native-sessions.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/subagent-native-sessions.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"capabilities":{},"name":"Fix the build","prompt":"Make the build pass","sessionUpdate":"subagent_spawned","subagentSessionId":"agent_n","task":"Make the build pass"}}}
--- a/src/tests/acp-scenarios/snapshots/air/subagent-nested.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/subagent-nested.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"capabilities":{},"name":"Plan the work","prompt":"Plan it","sessionUpdate":"subagent_spawned","subagentSessionId":"agent_outer","task":"Plan it"}}}
--- a/src/tests/acp-scenarios/snapshots/air/subagent-task-legacy.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/subagent-task-legacy.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"capabilities":{},"name":"Explore code","prompt":"Find the parser","sessionUpdate":"subagent_spawned","subagentSessionId":"agent_1","task":"Find the parser"}}}
--- a/src/tests/acp-scenarios/snapshots/air/subagent-transcript-extension.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/subagent-transcript-extension.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"capabilities":{},"name":"Summarize","prompt":"Summarize the repo","sessionUpdate":"subagent_spawned","subagentSessionId":"agent_t","task":"Summarize the repo"}}}
--- a/src/tests/acp-scenarios/snapshots/air/task-create-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/task-create-update.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"entries":[{"content":"Write tests","priority":"medium","status":"pending"}],"sessionUpdate":"plan"}}}
--- a/src/tests/acp-scenarios/snapshots/air/task-output-and-stop.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/task-output-and-stop.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"TaskOutput"}},"content":[],"kind":"other","name":"TaskOutput","sessionUpdate":"tool_call","status":"pending","title":"TaskOutput","toolCallId":"toolu_out"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
--- a/src/tests/acp-scenarios/snapshots/air/text-and-thinking.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/text-and-thinking.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"content":{"text":"Let me thin","type":"text"},"messageId":"msg_text","sessionUpdate":"agent_thought_chunk"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"content":{"text":"k about it.","type":"text"},"messageId":"msg_text","sessionUpdate":"agent_thought_chunk"}}}
--- a/src/tests/acp-scenarios/snapshots/air/todo-write.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/todo-write.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"entries":[{"content":"Writing tests","priority":"medium","status":"in_progress"},{"content":"Ship","priority":"medium","status":"pending"}],"sessionUpdate":"plan"}}}
--- a/src/tests/acp-scenarios/snapshots/air/tool-progress.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/tool-progress.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"},"terminal_info":{"terminal_id":"toolu_slow"}},"content":[{"terminalId":"toolu_slow","type":"terminal"}],"kind":"execute","name":"Bash","sessionUpdate":"tool_call","status":"pending","title":"Terminal","toolCallId":"toolu_slow"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
--- a/src/tests/acp-scenarios/snapshots/air/web-fetch-and-search.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/web-fetch-and-search.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"WebFetch"}},"content":[],"kind":"fetch","name":"WebFetch","sessionUpdate":"tool_call","status":"pending","title":"Fetch","toolCallId":"toolu_fetch"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"sessionUpdate":"tool_call_update","title":"Fetch https://example.com","toolCallId":"toolu_fetch"}}}
--- a/src/tests/acp-scenarios/snapshots/air/write-existing.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/write-existing.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Write"}},"content":[],"kind":"edit","locations":[],"name":"Write","sessionUpdate":"tool_call","status":"pending","title":"Preparing file…","toolCallId":"toolu_write"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"locations":[{"path":"<cwd>/old.ts"}],"sessionUpdate":"tool_call_update","title":"Write old.ts","toolCallId":"toolu_write"}}}
--- a/src/tests/acp-scenarios/snapshots/air/write-new.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/write-new.jsonl
@@ -1,4 +1,4 @@
-{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[],"sessionUpdate":"available_commands_update"}}}
+{"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Write"}},"content":[],"kind":"edit","locations":[],"name":"Write","sessionUpdate":"tool_call","status":"pending","title":"Preparing file…","toolCallId":"toolu_write"}}}
 {"kind":"sessionUpdate","payload":{"sessionId":"<session>","update":{"locations":[{"path":"<cwd>/new.ts"}],"sessionUpdate":"tool_call_update","title":"Write new.ts","toolCallId":"toolu_write"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/ask-user-question.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/ask-user-question.jsonl
@@ -0,0 +1,16 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"AskUserQuestion"}},"content":[],"kind":"other","name":"AskUserQuestion","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Asking for your input","toolCallId":"toolu_ask"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"AskUserQuestion"}},"content":[{"content":{"text":"Which database?","type":"text"},"type":"content"}],"rawInput":{"questions":[{"header":"Database","multiSelect":false,"options":[{"description":"Relational","label":"Postgres","preview":"CREATE TABLE t ();"},{"description":"Key-value","label":"Redis"}],"question":"Which database?"}]},"sessionUpdate":"tool_call_update","title":"Which database?","toolCallId":"toolu_ask"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"elicitation/create","payload":{"message":"Which database?","mode":"form","requestedSchema":{"properties":{"question_0":{"oneOf":[{"_meta":{"_claude/askUserQuestionOption":{"preview":"CREATE TABLE t ();"}},"const":"Postgres","description":"Relational","title":"Postgres"},{"const":"Redis","description":"Key-value","title":"Redis"}],"title":"Database","type":"string"},"question_0_custom":{"description":"Type your own answer, or add a note to the option you chose above (optional).","title":"Other","type":"string"}},"type":"object"},"sessionId":"<session>","toolCallId":"toolu_ask"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"AskUserQuestion"}},"content":[{"content":{"text":"User has answered your questions: \"Which database?\"=\"Postgres\".","type":"text"},"type":"content"}],"rawOutput":"User has answered your questions: \"Which database?\"=\"Postgres\".","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_ask"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/async-task-ends-before-tool-id.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/async-task-ends-before-tool-id.jsonl
@@ -0,0 +1,7 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/async-task-held-until-tool-id.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/async-task-held-until-tool-id.jsonl
@@ -0,0 +1,7 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/async-task-released-at-turn-end.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/async-task-released-at-turn-end.jsonl
@@ -0,0 +1,7 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/bash-background.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/bash-background.jsonl
@@ -0,0 +1,19 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"terminal_update","terminalId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"content":[{"terminalId":"toolu_bg","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Terminal","toolCallId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"command":"sleep 100","sessionUpdate":"terminal_update","terminalId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"sleep 100"},"sessionUpdate":"tool_call_update","title":"sleep 100","toolCallId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"sleep 100","description":"Wait"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"sleep 100","description":"Wait","run_in_background":true},"sessionUpdate":"tool_call_update","toolCallId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"output":{"data":"Q29tbWFuZCBydW5uaW5nIGluIGJhY2tncm91bmQgd2l0aCBJRDogYmFzaF8xLiBPdXRwdXQgaXMgYmVpbmcgd3JpdHRlbiB0bzogL3RtcC90YXNrcy9iYXNoXzEub3V0cHV0LiBZb3Ugd2lsbCBiZSBub3RpZmllZCB3aGVuIGl0IGNvbXBsZXRlcy4="},"sessionUpdate":"terminal_update","terminalId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"exitStatus":{},"sessionUpdate":"terminal_update","terminalId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/bash-error.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/bash-error.jsonl
@@ -0,0 +1,18 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"terminal_update","terminalId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"content":[{"terminalId":"toolu_bash","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Terminal","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"command":"false","sessionUpdate":"terminal_update","terminalId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"false"},"sessionUpdate":"tool_call_update","title":"false","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"false","description":"Fail"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"output":{"data":"RXhpdCBjb2RlIDEKYm9vbQ=="},"sessionUpdate":"terminal_update","terminalId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"exitStatus":{"exitCode":1},"sessionUpdate":"terminal_update","terminalId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"sessionUpdate":"tool_call_update","status":"failed","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/bash-foreground.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/bash-foreground.jsonl
@@ -0,0 +1,25 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"terminal_update","terminalId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"content":[{"terminalId":"toolu_bash","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Terminal","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"command":"ls -la","sessionUpdate":"terminal_update","terminalId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"ls -la"},"sessionUpdate":"tool_call_update","title":"ls -la","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"ls -la","description":"List files"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"content":[{"terminalId":"toolu_bash","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{"command":"ls -la","description":"List files"},"status":"pending","title":"ls -la","toolCallId":"toolu_bash"},"type":"tool_call"},"title":"ls -la"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"output":{"data":"YS50cwpiLnRz"},"sessionUpdate":"terminal_update","terminalId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"exitStatus":{"exitCode":0},"sessionUpdate":"terminal_update","terminalId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash","toolResponse":{"interrupted":false,"isImage":false,"stderr":"","stdout":"a.ts\nb.ts"}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"Do","type":"text"},"messageId":"msg_done","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"ne.","type":"text"},"messageId":"msg_done","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/compaction-failed-legacy.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/compaction-failed-legacy.jsonl
@@ -0,0 +1,9 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","sessionUpdate":"compaction_update","status":"in_progress"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","error":"Context too small","sessionUpdate":"compaction_update","status":"failed"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/compaction-legacy.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/compaction-legacy.jsonl
@@ -0,0 +1,12 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","sessionUpdate":"compaction_update","status":"in_progress"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","content":{"text":"The summary.","type":"text"},"sessionUpdate":"compaction_summary_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","sessionUpdate":"compaction_update","status":"completed"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"usage_update","size":200000,"used":100}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":100}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/compaction-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/compaction-update.jsonl
@@ -0,0 +1,12 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","sessionUpdate":"compaction_update","status":"in_progress"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","content":{"text":"The summary.","type":"text"},"sessionUpdate":"compaction_summary_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"compactionId":"00000000-0000-4000-8000-000000000001","sessionUpdate":"compaction_update","status":"completed"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"usage_update","size":200000,"used":100}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":100}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/edit-rejected.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/edit-rejected.jsonl
@@ -0,0 +1,18 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"content":[],"kind":"edit","locations":[],"name":"Edit","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Edit","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"locations":[{"path":"<cwd>/src/app.ts"}],"rawInput":{"file_path":"<cwd>/src/app.ts"},"sessionUpdate":"tool_call_update","title":"Edit src/app.ts","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"rawInput":{"file_path":"<cwd>/src/app.ts","old_string":"value = 1"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"rawInput":{"file_path":"<cwd>/src/app.ts","new_string":"value = 2","old_string":"value = 1"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"content":[{"changes":[{"fileType":"text","operation":"modify","path":"<cwd>/src/app.ts"}],"patch":{"format":"git_patch","text":"diff --git <cwd>/src/app.ts <cwd>/src/app.ts\n--- <cwd>/src/app.ts\n+++ <cwd>/src/app.ts\n@@ -1 +1 @@\n-const value = 1;\n+const value = 2;\n"},"type":"diff"}],"kind":"edit","locations":[{"path":"<cwd>/src/app.ts"}],"name":"Edit","rawInput":{"file_path":"<cwd>/src/app.ts","new_string":"value = 2","old_string":"value = 1"},"status":"pending","title":"Edit src/app.ts","toolCallId":"toolu_edit"},"type":"tool_call"},"title":"Edit src/app.ts"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"content":[{"content":{"text":"```\nThe user doesn't want to proceed with this tool use. The tool use was rejected.\n```","type":"text"},"type":"content"}],"rawOutput":"The user doesn't want to proceed with this tool use. The tool use was rejected.","sessionUpdate":"tool_call_update","status":"failed","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/edit-with-permission.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/edit-with-permission.jsonl
@@ -0,0 +1,19 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"content":[],"kind":"edit","locations":[],"name":"Edit","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Edit","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"locations":[{"path":"<cwd>/src/app.ts"}],"rawInput":{"file_path":"<cwd>/src/app.ts"},"sessionUpdate":"tool_call_update","title":"Edit src/app.ts","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"rawInput":{"file_path":"<cwd>/src/app.ts","old_string":"const value = 1;"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"rawInput":{"file_path":"<cwd>/src/app.ts","new_string":"const value = 2;","old_string":"const value = 1;"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"content":[{"changes":[{"fileType":"text","operation":"modify","path":"<cwd>/src/app.ts"}],"patch":{"format":"git_patch","text":"diff --git <cwd>/src/app.ts <cwd>/src/app.ts\n--- <cwd>/src/app.ts\n+++ <cwd>/src/app.ts\n@@ -1,3 +1,3 @@\n line 1\n-const value = 1;\n+const value = 2;\n line 3\n"},"type":"diff"}],"kind":"edit","locations":[{"path":"<cwd>/src/app.ts"}],"name":"Edit","rawInput":{"file_path":"<cwd>/src/app.ts","new_string":"const value = 2;","old_string":"const value = 1;"},"status":"pending","title":"Edit src/app.ts","toolCallId":"toolu_edit"},"type":"tool_call"},"title":"Edit src/app.ts"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"rawOutput":"The file <cwd>/src/app.ts has been updated successfully.","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit","toolResponse":{"filePath":"<cwd>/src/app.ts","newString":"const value = 2;","oldString":"const value = 1;","originalFile":"line 1\nconst value = 1;\nline 3\n","replaceAll":false,"structuredPatch":[{"lines":[" line 1","-const value = 1;","+const value = 2;"," line 3"],"newLines":3,"newStart":1,"oldLines":3,"oldStart":1}],"userModified":false}}},"locations":[{"line":1,"path":"<cwd>/src/app.ts"}],"sessionUpdate":"tool_call_update","toolCallId":"toolu_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/exit-plan-approve.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/exit-plan-approve.jsonl
@@ -0,0 +1,17 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"ExitPlanMode"}},"content":[],"kind":"switch_mode","name":"ExitPlanMode","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Approve Plan","toolCallId":"toolu_plan"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"ExitPlanMode"}},"content":[{"content":{"text":"# Plan\n1. Do it","type":"text"},"type":"content"}],"rawInput":{"plan":"# Plan\n1. Do it"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_plan"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes, manually approve edits","optionId":"exit-plan-default"},{"kind":"allow_always","name":"Yes, clear context (0% used) and use auto mode","optionId":"exit-plan-clear-auto"},{"kind":"allow_always","name":"Yes, and use auto mode","optionId":"exit-plan-auto"},{"kind":"allow_always","name":"Yes, and bypass permissions","optionId":"exit-plan-bypass"},{"kind":"reject_once","name":"No, keep planning","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"content":[{"content":{"text":"# Plan\n1. Do it","type":"text"},"type":"content"}],"kind":"switch_mode","name":"ExitPlanMode","rawInput":{"plan":"# Plan\n1. Do it"},"status":"pending","title":"Approve Plan","toolCallId":"toolu_plan"},"type":"tool_call"},"title":"Ready to code?"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionUpdate":"config_option_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"ExitPlanMode"}},"rawOutput":"User has approved your plan. You can now start coding.\n\n## Approved Plan:\n# Plan\n1. Do it","sessionUpdate":"tool_call_update","status":"completed","title":"Exited Plan Mode","toolCallId":"toolu_plan"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/exit-plan-reject.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/exit-plan-reject.jsonl
@@ -0,0 +1,16 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"ExitPlanMode"}},"content":[],"kind":"switch_mode","name":"ExitPlanMode","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Approve Plan","toolCallId":"toolu_plan"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"ExitPlanMode"}},"content":[{"content":{"text":"# Plan\n1. Do it","type":"text"},"type":"content"}],"rawInput":{"plan":"# Plan\n1. Do it"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_plan"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes, manually approve edits","optionId":"exit-plan-default"},{"kind":"allow_always","name":"Yes, clear context (0% used) and use auto mode","optionId":"exit-plan-clear-auto"},{"kind":"allow_always","name":"Yes, and use auto mode","optionId":"exit-plan-auto"},{"kind":"allow_always","name":"Yes, and bypass permissions","optionId":"exit-plan-bypass"},{"kind":"reject_once","name":"No, keep planning","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"content":[{"content":{"text":"# Plan\n1. Do it","type":"text"},"type":"content"}],"kind":"switch_mode","name":"ExitPlanMode","rawInput":{"plan":"# Plan\n1. Do it"},"status":"pending","title":"Approve Plan","toolCallId":"toolu_plan"},"type":"tool_call"},"title":"Ready to code?"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"ExitPlanMode"}},"content":[{"content":{"text":"```\n```\nThe user doesn't want to proceed with this tool use.\n```\n```","type":"text"},"type":"content"}],"rawOutput":"The user doesn't want to proceed with this tool use.","sessionUpdate":"tool_call_update","status":"failed","toolCallId":"toolu_plan"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/goal.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/goal.jsonl
@@ -0,0 +1,7 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"/goal Ship the feature","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/grep-and-glob.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/grep-and-glob.jsonl
@@ -0,0 +1,20 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Grep"}},"content":[],"kind":"search","name":"Grep","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"grep","toolCallId":"toolu_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Grep"}},"rawInput":{"pattern":"value"},"sessionUpdate":"tool_call_update","title":"grep \"value\"","toolCallId":"toolu_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Grep"}},"rawInput":{"path":"src","pattern":"value"},"sessionUpdate":"tool_call_update","title":"grep \"value\" src","toolCallId":"toolu_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Grep"}},"rawInput":{"output_mode":"content","path":"src","pattern":"value"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Grep"}},"rawInput":{"-n":true,"output_mode":"content","path":"src","pattern":"value"},"sessionUpdate":"tool_call_update","title":"grep -n \"value\" src","toolCallId":"toolu_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Grep"}},"content":[{"content":{"text":"src/app.ts:2:const value = 1;","type":"text"},"type":"content"}],"rawOutput":"src/app.ts:2:const value = 1;","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Glob"}},"content":[],"kind":"search","locations":[],"name":"Glob","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Find","toolCallId":"toolu_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Glob"}},"rawInput":{"pattern":"**/*.ts"},"sessionUpdate":"tool_call_update","title":"Find `**/*.ts`","toolCallId":"toolu_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Glob"}},"content":[{"content":{"text":"src/app.ts\nsrc/b.ts","type":"text"},"type":"content"}],"rawOutput":"src/app.ts\nsrc/b.ts","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/mcp-tool.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/mcp-tool.jsonl
@@ -0,0 +1,17 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"mcp__docs__search"}},"content":[],"kind":"other","name":"mcp__docs__search","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"mcp__docs__search","toolCallId":"toolu_mcp"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"mcp__docs__search"}},"rawInput":{"q":"acp"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_mcp"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"_meta":{"claudeCode":{"mcpServer":{"name":"docs","source":"project"},"toolName":"mcp__docs__search"}},"content":[],"kind":"other","name":"mcp__docs__search","rawInput":{"q":"acp"},"status":"pending","title":"mcp__docs__search","toolCallId":"toolu_mcp"},"type":"tool_call"},"title":"mcp__docs__search"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"mcp__docs__search"}},"content":[{"content":{"text":"Found 2 documents.","type":"text"},"type":"content"}],"rawOutput":[{"text":"Found 2 documents.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_mcp"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"mcp__docs__search","toolResponse":[{"text":"Found 2 documents.","type":"text"}]}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_mcp"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/memory-recall.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/memory-recall.jsonl
@@ -0,0 +1,9 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"memory_recall","toolResponse":{"mode":"select"}}},"kind":"read","locations":[{"path":"/memory/a.md"},{"path":"/memory/b.md"}],"sessionUpdate":"tool_call_update","status":"completed","title":"Recalled 2 memories","toolCallId":"00000000-0000-4000-8000-000000000001"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"memory_recall","toolResponse":{"mode":"synthesize"}}},"content":[{"content":{"text":"The user prefers tabs.","type":"text"},"type":"content"}],"kind":"read","sessionUpdate":"tool_call_update","status":"completed","title":"Recalled synthesized memory","toolCallId":"00000000-0000-4000-8000-000000000002"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/network-permission.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/network-permission.jsonl
@@ -0,0 +1,11 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"SandboxNetworkAccess"}},"content":[],"kind":"other","name":"SandboxNetworkAccess","rawInput":{"host":"example.com"},"sessionUpdate":"tool_call_update","status":"pending","title":"SandboxNetworkAccess","toolCallId":"toolu_net"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"description":"Reason: Sandbox blocks network","options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"content":[{"content":{"text":"```json\n{\n  \"host\": \"example.com\"\n}\n```","type":"text"},"type":"content"}],"kind":"other","name":"SandboxNetworkAccess","rawInput":{"host":"example.com"},"status":"pending","title":"example.com","toolCallId":"toolu_net"},"type":"tool_call"},"title":"example.com"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/notebook-edit.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/notebook-edit.jsonl
@@ -0,0 +1,19 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"NotebookEdit"}},"content":[],"kind":"other","name":"NotebookEdit","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"NotebookEdit","toolCallId":"toolu_nb"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"NotebookEdit"}},"rawInput":{"notebook_path":"<cwd>/n.ipynb"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_nb"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"NotebookEdit"}},"rawInput":{"cell_id":"cell-1","notebook_path":"<cwd>/n.ipynb"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_nb"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"NotebookEdit"}},"rawInput":{"cell_id":"cell-1","new_source":"print('hi')","notebook_path":"<cwd>/n.ipynb"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_nb"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"NotebookEdit"}},"rawInput":{"cell_id":"cell-1","edit_mode":"replace","new_source":"print('hi')","notebook_path":"<cwd>/n.ipynb"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_nb"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"content":[],"kind":"other","name":"NotebookEdit","rawInput":{"cell_id":"cell-1","edit_mode":"replace","new_source":"print('hi')","notebook_path":"<cwd>/n.ipynb"},"status":"pending","title":"NotebookEdit","toolCallId":"toolu_nb"},"type":"tool_call"},"title":"NotebookEdit"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"NotebookEdit"}},"content":[{"content":{"text":"Updated cell cell-1 with print('hi')","type":"text"},"type":"content"}],"rawOutput":"Updated cell cell-1 with print('hi')","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_nb"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/permission-denied.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/permission-denied.jsonl
@@ -0,0 +1,18 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"terminal_update","terminalId":"toolu_denied"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"content":[{"terminalId":"toolu_denied","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Terminal","toolCallId":"toolu_denied"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"command":"rm -rf /","sessionUpdate":"terminal_update","terminalId":"toolu_denied"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"rm -rf /"},"sessionUpdate":"tool_call_update","title":"rm -rf /","toolCallId":"toolu_denied"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash","toolResponse":{"decisionReason":"Denied by rule Bash(rm:*)","decisionReasonType":"rule","message":"Permission to use Bash has been denied."}}},"content":[{"content":{"text":"Permission denied: Denied by rule Bash(rm:*)","type":"text"},"type":"content"}],"sessionUpdate":"tool_call_update","status":"failed","toolCallId":"toolu_denied"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"output":{"data":"UGVybWlzc2lvbiB0byB1c2UgQmFzaCBoYXMgYmVlbiBkZW5pZWQu"},"sessionUpdate":"terminal_update","terminalId":"toolu_denied"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"exitStatus":{},"sessionUpdate":"terminal_update","terminalId":"toolu_denied"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"content":[{"terminalId":"toolu_denied","type":"terminal"}],"sessionUpdate":"tool_call_update","toolCallId":"toolu_denied"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/rate-limit-and-origin.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/rate-limit-and-origin.jsonl
@@ -0,0 +1,13 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"Work","type":"text"},"messageId":"msg_rate","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"ing.","type":"text"},"messageId":"msg_rate","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6","_claude/rateLimit":{"resetsAt":1700000000,"status":"allowed_warning","utilization":0.9}},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6","_claude/origin":{"kind":"human"}},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/read.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/read.jsonl
@@ -0,0 +1,14 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Read"}},"content":[],"kind":"read","locations":[],"name":"Read","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Read File","toolCallId":"toolu_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Read"}},"locations":[{"line":1,"path":"<cwd>/a.ts"}],"rawInput":{"file_path":"<cwd>/a.ts"},"sessionUpdate":"tool_call_update","title":"Read a.ts","toolCallId":"toolu_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Read"}},"content":[{"content":{"text":"```\n1\tconst a = 1;\n```","type":"text"},"type":"content"}],"rawOutput":"1\tconst a = 1;\n<system-reminder>x</system-reminder>","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Read","toolResponse":{"file":{"content":"const a = 1;\n","filePath":"<cwd>/a.ts","numLines":1,"startLine":1,"totalLines":1},"type":"text"}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/session-load-replay.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/session-load-replay.jsonl
@@ -0,0 +1,20 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"messageId":"00000000-0000-4000-8000-00000000c001","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"Fix the bug","type":"text"},"messageId":"00000000-0000-4000-8000-00000000c001","sessionUpdate":"user_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"messageId":"msg_r1","sessionUpdate":"agent_thought"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"Check the file.","type":"text"},"messageId":"msg_r1","sessionUpdate":"agent_thought_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"messageId":"msg_r1","sessionUpdate":"agent_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"I will edit it.","type":"text"},"messageId":"msg_r1","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"command":"ls","sessionUpdate":"terminal_update","terminalId":"toolu_r_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"content":[{"terminalId":"toolu_r_bash","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{"command":"ls","description":"List"},"sessionUpdate":"tool_call_update","status":"pending","title":"ls","toolCallId":"toolu_r_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"content":[],"kind":"edit","locations":[{"path":"<cwd>/src/app.ts"}],"name":"Edit","rawInput":{"file_path":"<cwd>/src/app.ts","new_string":"b","old_string":"a"},"sessionUpdate":"tool_call_update","status":"pending","title":"Edit src/app.ts","toolCallId":"toolu_r_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[{"content":{"text":"Look around","type":"text"},"type":"content"}],"kind":"think","name":"Task","rawInput":{"description":"Explore","prompt":"Look around"},"sessionUpdate":"tool_call_update","status":"pending","title":"Explore","toolCallId":"toolu_r_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"output":{"data":"YXBwLnRz"},"sessionUpdate":"terminal_update","terminalId":"toolu_r_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"exitStatus":{"exitCode":0},"sessionUpdate":"terminal_update","terminalId":"toolu_r_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"content":[{"terminalId":"toolu_r_bash","type":"terminal"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_r_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Edit"}},"rawOutput":"The file <cwd>/src/app.ts has been updated successfully.","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_r_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[{"content":{"text":"Report.","type":"text"},"type":"content"}],"rawOutput":"Report.","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_r_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"messageId":"msg_r2","sessionUpdate":"agent_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"Fixed.","type":"text"},"messageId":"msg_r2","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"response","method":"session/resume","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}]}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/session-setup.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/session-setup.jsonl
@@ -0,0 +1,3 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/skill.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/skill.jsonl
@@ -0,0 +1,14 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Skill"}},"content":[],"kind":"other","name":"Skill","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Load skill","toolCallId":"toolu_skill"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Skill"}},"rawInput":{"skill":"commits"},"sessionUpdate":"tool_call_update","title":"Load skill: commits","toolCallId":"toolu_skill"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Skill"}},"rawOutput":"Launching skill: commits","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_skill"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Skill","toolResponse":{"commandName":"commits","success":true}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_skill"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/subagent-agent-async.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/subagent-agent-async.jsonl
@@ -0,0 +1,19 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[],"kind":"think","name":"Agent","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Background review"},"sessionUpdate":"tool_call_update","title":"Background review","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Background review","prompt":"Review the diff"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Background review","prompt":"Review the diff","subagent_type":"general-purpose"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"Review the diff","type":"text"},"type":"content"}],"rawInput":{"description":"Background review","prompt":"Review the diff","run_in_background":true,"subagent_type":"general-purpose"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"Async agent launched successfully.","type":"text"},"type":"content"}],"rawOutput":"Async agent launched successfully.\nagentId: a2 (use SendMessage to continue)","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent","toolResponse":{"agentId":"a2","description":"Background review","isAsync":true,"outputFile":"/tmp/tasks/a2.output","prompt":"Review the diff","status":"async_launched"}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_agent"}},"content":{"text":"Reviewi","type":"text"},"messageId":"msg_async_sub","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_agent"}},"content":{"text":"ng now.","type":"text"},"messageId":"msg_async_sub","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/subagent-late-child-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/subagent-late-child-update.jsonl
@@ -0,0 +1,19 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[],"kind":"think","name":"Agent","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_late"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Check the logs"},"sessionUpdate":"tool_call_update","title":"Check the logs","toolCallId":"toolu_late"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Check the logs","prompt":"Check logs"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_late"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"Check logs","type":"text"},"type":"content"}],"rawInput":{"description":"Check the logs","prompt":"Check logs","subagent_type":"general-purpose"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_late"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_late","toolName":"Read"}},"content":[],"kind":"read","locations":[],"name":"Read","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Read File","toolCallId":"toolu_late_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_late","toolName":"Read"}},"locations":[{"line":1,"path":"/var/log/app.log"}],"rawInput":{"file_path":"/var/log/app.log"},"sessionUpdate":"tool_call_update","title":"Read /var/log/app.log","toolCallId":"toolu_late_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"The logs are clean.","type":"text"},"type":"content"}],"rawOutput":[{"text":"The logs are clean.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_late"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Read","toolResponse":{"elapsedTimeSeconds":4}}},"sessionUpdate":"tool_call_update","status":"in_progress","toolCallId":"toolu_late_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_late","toolName":"Read"}},"content":[{"content":{"text":"```\n1\tok\n```","type":"text"},"type":"content"}],"rawOutput":"1\tok","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_late_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/subagent-native-sessions.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/subagent-native-sessions.jsonl
@@ -0,0 +1,32 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[],"kind":"think","name":"Agent","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_native"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Fix the build"},"sessionUpdate":"tool_call_update","title":"Fix the build","toolCallId":"toolu_native"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Fix the build","prompt":"Make the build pass"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_native"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"Make the build pass","type":"text"},"type":"content"}],"rawInput":{"description":"Fix the build","prompt":"Make the build pass","subagent_type":"general-purpose"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_native"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native"}},"content":{"text":"Running t","type":"text"},"messageId":"msg_native_sub_1","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native"}},"content":{"text":"he build.","type":"text"},"messageId":"msg_native_sub_1","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Grep"}},"content":[],"kind":"search","name":"Grep","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"grep","toolCallId":"toolu_native_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Grep"}},"rawInput":{"pattern":"TODO"},"sessionUpdate":"tool_call_update","title":"grep \"TODO\"","toolCallId":"toolu_native_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Grep"}},"rawInput":{"path":"/src","pattern":"TODO"},"sessionUpdate":"tool_call_update","title":"grep \"TODO\" /src","toolCallId":"toolu_native_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Grep"}},"content":[{"content":{"text":"src/a.ts","type":"text"},"type":"content"}],"rawOutput":"src/a.ts","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_native_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"terminal_update","terminalId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Bash"}},"content":[{"terminalId":"toolu_native_bash","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Terminal","toolCallId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"command":"make","sessionUpdate":"terminal_update","terminalId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Bash"}},"rawInput":{"command":"make"},"sessionUpdate":"tool_call_update","title":"make","toolCallId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Bash"}},"rawInput":{"command":"make","description":"Build"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Bash"}},"content":[{"terminalId":"toolu_native_bash","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{"command":"make","description":"Build"},"status":"pending","title":"make","toolCallId":"toolu_native_bash"},"type":"tool_call"},"title":"make"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"output":{"data":"bWFrZTogKioqIEVycm9yIDI="},"sessionUpdate":"terminal_update","terminalId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"exitStatus":{},"sessionUpdate":"terminal_update","terminalId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native","toolName":"Bash"}},"sessionUpdate":"tool_call_update","status":"failed","toolCallId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"```\nThe build still fails.\n```","type":"text"},"type":"content"}],"rawOutput":[{"text":"The build still fails.","type":"text"}],"sessionUpdate":"tool_call_update","status":"failed","toolCallId":"toolu_native"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/subagent-nested.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/subagent-nested.jsonl
@@ -0,0 +1,25 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[],"kind":"think","name":"Agent","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_outer"}}}
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+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"Plan it","type":"text"},"type":"content"}],"rawInput":{"description":"Plan the work","prompt":"Plan it","subagent_type":"Plan"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_outer"}}}
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+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer","toolName":"Agent"}},"content":[{"content":{"text":"Read spec.md","type":"text"},"type":"content"}],"rawInput":{"description":"Read the spec","prompt":"Read spec.md","subagent_type":"Explore"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_inner"}}}
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+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_inner","toolName":"Read"}},"locations":[{"line":1,"path":"/spec.md"}],"rawInput":{"file_path":"/spec.md"},"sessionUpdate":"tool_call_update","title":"Read /spec.md","toolCallId":"toolu_grandchild_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_inner","toolName":"Read"}},"content":[{"content":{"text":"```\n1\tspec\n```","type":"text"},"type":"content"}],"rawOutput":"1\tspec","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_grandchild_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer","toolName":"Agent"}},"content":[{"content":{"text":"The spec says X.","type":"text"},"type":"content"}],"rawOutput":[{"text":"The spec says X.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_inner"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer"}},"content":{"text":"Plan:","type":"text"},"messageId":"msg_outer_text","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer"}},"content":{"text":" do X.","type":"text"},"messageId":"msg_outer_text","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"Plan: do X.","type":"text"},"type":"content"}],"rawOutput":[{"text":"Plan: do X.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_outer"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/subagent-task-legacy.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/subagent-task-legacy.jsonl
@@ -0,0 +1,44 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[],"kind":"think","name":"Task","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"rawInput":{"description":"Explore code"},"sessionUpdate":"tool_call_update","title":"Explore code","toolCallId":"toolu_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"rawInput":{"description":"Explore code","prompt":"Find the parser"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[{"content":{"text":"Find the parser","type":"text"},"type":"content"}],"rawInput":{"description":"Explore code","prompt":"Find the parser","subagent_type":"Explore"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task"}},"content":{"text":"Looking for","type":"text"},"messageId":"msg_sub_1","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task"}},"content":{"text":" the parser.","type":"text"},"messageId":"msg_sub_1","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Read"}},"content":[],"kind":"read","locations":[],"name":"Read","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Read File","toolCallId":"toolu_sub_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Read"}},"locations":[{"line":1,"path":"/x.ts"}],"rawInput":{"file_path":"/x.ts"},"sessionUpdate":"tool_call_update","title":"Read /x.ts","toolCallId":"toolu_sub_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task","toolResponse":{"elapsedTimeSeconds":3,"subagentType":"Explore"}}},"sessionUpdate":"tool_call_update","status":"in_progress","toolCallId":"toolu_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Read"}},"content":[{"content":{"text":"```\n1\tparser\n```","type":"text"},"type":"content"}],"rawOutput":"1\tparser","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_sub_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"terminal_update","terminalId":"toolu_sub_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Bash"}},"content":[{"terminalId":"toolu_sub_bash","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Terminal","toolCallId":"toolu_sub_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"command":"rg parser","sessionUpdate":"terminal_update","terminalId":"toolu_sub_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Bash"}},"rawInput":{"command":"rg parser"},"sessionUpdate":"tool_call_update","title":"rg parser","toolCallId":"toolu_sub_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Bash"}},"rawInput":{"command":"rg parser","description":"Search"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_sub_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Bash"}},"content":[{"terminalId":"toolu_sub_bash","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{"command":"rg parser","description":"Search"},"status":"pending","title":"rg parser","toolCallId":"toolu_sub_bash"},"type":"tool_call"},"title":"rg parser"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"output":{"data":"eC50cw=="},"sessionUpdate":"terminal_update","terminalId":"toolu_sub_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"exitStatus":{"exitCode":0},"sessionUpdate":"terminal_update","terminalId":"toolu_sub_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Bash"}},"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_sub_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Edit"}},"content":[],"kind":"edit","locations":[],"name":"Edit","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Edit","toolCallId":"toolu_sub_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Edit"}},"locations":[{"path":"<cwd>/x.ts"}],"rawInput":{"file_path":"<cwd>/x.ts"},"sessionUpdate":"tool_call_update","title":"Edit x.ts","toolCallId":"toolu_sub_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Edit"}},"rawInput":{"file_path":"<cwd>/x.ts","old_string":"a"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_sub_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Edit"}},"rawInput":{"file_path":"<cwd>/x.ts","new_string":"b","old_string":"a"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_sub_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"requires_action"}}}
+{"kind":"request","method":"session/request_permission","payload":{"options":[{"kind":"allow_once","name":"Yes","optionId":"allow-once"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Edit"}},"content":[],"kind":"edit","locations":[{"path":"<cwd>/x.ts"}],"name":"Edit","rawInput":{"file_path":"<cwd>/x.ts","new_string":"b","old_string":"a"},"status":"pending","title":"Edit x.ts","toolCallId":"toolu_sub_edit"},"type":"tool_call"},"title":"Edit x.ts"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Edit"}},"rawOutput":"The file has been updated.","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_sub_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task","toolName":"Edit","toolResponse":{"filePath":"<cwd>/x.ts","newString":"b","oldString":"a","originalFile":"a\n","replaceAll":false,"structuredPatch":[{"lines":["-a","+b"],"newLines":1,"newStart":1,"oldLines":1,"oldStart":1}],"userModified":false}}},"content":[{"changes":[{"fileType":"text","operation":"modify","path":"<cwd>/x.ts"}],"patch":{"format":"git_patch","text":"diff --git <cwd>/x.ts <cwd>/x.ts\n--- <cwd>/x.ts\n+++ <cwd>/x.ts\n@@ -1 +1 @@\n-a\n+b\n"},"type":"diff"}],"locations":[{"line":1,"path":"<cwd>/x.ts"}],"sessionUpdate":"tool_call_update","toolCallId":"toolu_sub_edit"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task"}},"content":{"text":"Foun","type":"text"},"messageId":"msg_sub_2","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_task"}},"content":{"text":"d it.","type":"text"},"messageId":"msg_sub_2","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[{"content":{"text":"The parser is in x.ts.","type":"text"},"type":"content"}],"rawOutput":[{"text":"The parser is in x.ts.\nagentId: a1 (use SendMessage to continue)","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task","toolResponse":{"agentId":"a1","content":[{"text":"The parser is in x.ts.","type":"text"}],"prompt":"Find the parser","status":"completed","totalDurationMs":10,"totalTokens":5,"totalToolUseCount":1}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/subagent-transcript-extension.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/subagent-transcript-extension.jsonl
@@ -0,0 +1,22 @@
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"providers":{},"session":{"additionalDirectories":{},"delete":{},"fork":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"response","method":"session/prompt","payload":{"messageId":"<id-1>"}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[],"kind":"think","name":"Task","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"rawInput":{"description":"Summarize"},"sessionUpdate":"tool_call_update","title":"Summarize","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"rawInput":{"description":"Summarize","prompt":"Summarize the repo"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[{"content":{"text":"Summarize the repo","type":"text"},"type":"content"}],"rawInput":{"description":"Summarize","prompt":"Summarize the repo","subagent_type":"Explore"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript"}},"content":{"text":"Look at t","type":"text"},"messageId":"msg_transcript_sub","sessionUpdate":"agent_thought_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript"}},"content":{"text":"he layout.","type":"text"},"messageId":"msg_transcript_sub","sessionUpdate":"agent_thought_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript"}},"content":{"text":"The repo has ","type":"text"},"messageId":"msg_transcript_sub","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript"}},"content":{"text":"two packages.","type":"text"},"messageId":"msg_transcript_sub","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript","toolName":"Glob"}},"content":[],"kind":"search","locations":[],"name":"Glob","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Find","toolCallId":"toolu_transcript_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript","toolName":"Glob"}},"rawInput":{"pattern":"*"},"sessionUpdate":"tool_call_update","title":"Find `*`","toolCallId":"toolu_transcript_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript","toolName":"Glob"}},"content":[{"content":{"text":"a\nb","type":"text"},"type":"content"}],"rawOutput":"a\nb","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_transcript_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[{"content":{"text":"Two packages.","type":"text"},"type":"content"}],"rawOutput":[{"text":"Two packages.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/Show More
+++ b/Show More