chore(main): release 0.86.0 (#1225 )

🤖 I have created a release *beep* *boop* --- ## [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](190a00f68f)) * **deps:** Bump @anthropic-ai/claude-agent-sdk to 0.3.287 ([#1224](https://github.com/agentclientprotocol/claude-agent-acp/issues/1224)) ([ddd5f54](ddd5f54187)) ### 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](d599333b72)) * drop queued prompts a cancel ends from Claude Code's queue ([#1228](https://github.com/agentclientprotocol/claude-agent-acp/issues/1228)) ([d83f28a](d83f28a403)) * end a cancelled turn when the force-cancel fires during an update ([#1243](https://github.com/agentclientprotocol/claude-agent-acp/issues/1243)) ([a44c486](a44c486019)) * end a closed session's turns before session/close answers ([#1242](https://github.com/agentclientprotocol/claude-agent-acp/issues/1242)) ([b1d6cfc](b1d6cfc6c9)) * end a held turn cancelled mid-followup at its interrupt's idle ([#1229](https://github.com/agentclientprotocol/claude-agent-acp/issues/1229)) ([d3e673b](d3e673b263)) * excessive message/token_count API calls when probing context window ([#1258](https://github.com/agentclientprotocol/claude-agent-acp/issues/1258)) ([5598efb](5598efbc8a)) * replay a session with a Write on the experimental ACP v2 surface ([#1238](https://github.com/agentclientprotocol/claude-agent-acp/issues/1238)) ([22139f7](22139f73c4)) * report a command's exit code only when the tool result says it ([#1252](https://github.com/agentclientprotocol/claude-agent-acp/issues/1252)) ([52a92be](52a92be959)) * restore main-thread agent config option ([#1250](https://github.com/agentclientprotocol/claude-agent-acp/issues/1250)) ([8589a9c](8589a9cf15)) --- 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: excessive message/token_count API calls when probing context window (#1258 )
2026-11-06 09:22:13 +00:00 · 2026-10-05 15:14:44 +02:00 · 2026-10-05 15:35:12 +04:00 · 2026-10-05 12:59:48 +02:00 · 2026-10-05 12:55:13 +02:00 · 2026-10-05 12:44:02 +02:00
137 changed files with 9821 additions and 650 deletions
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.85.0"
+  ".": "0.86.0"
 }
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,35 @@
 # Changelog

+## [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)


--- 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

--- a/package-lock.json
+++ b/package-lock.json
@@ -1,16 +1,16 @@
 {
  "name": "@agentclientprotocol/claude-agent-acp",
-  "version": "0.85.0",
+  "version": "0.86.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "@agentclientprotocol/claude-agent-acp",
-      "version": "0.85.0",
+      "version": "0.86.0",
      "license": "Apache-2.0",
      "dependencies": {
-        "@agentclientprotocol/sdk": "1.5.1",
-        "@anthropic-ai/claude-agent-sdk": "0.3.286",
+        "@agentclientprotocol/sdk": "1.7.0",
+        "@anthropic-ai/claude-agent-sdk": "0.3.287",
        "diff": "9.0.0",
        "zod": "4.6.5"
      },
@@ -39,31 +39,31 @@
      }
    },
    "node_modules/@agentclientprotocol/sdk": {
-      "version": "1.5.1",
-      "resolved": "https://registry.npmjs.org/@agentclientprotocol/sdk/-/sdk-1.5.1.tgz",
-      "integrity": "sha512-nSUIrC1fOR9+ppKfx9KdwjBBND2sAPzFHo4yVQrGbXZHnayUYpwL8CDVR5LSxbapY/oKMOzNP0wvwfyx3PS2KA==",
+      "version": "1.7.0",
+      "resolved": "https://registry.npmjs.org/@agentclientprotocol/sdk/-/sdk-1.7.0.tgz",
+      "integrity": "sha512-ZORuxsuEnLjRly7t6Ad7zAsWitjWsyprswyPUHz/yycPb+tTm3DGa8XheaHhRXqX8LS9snuxaYavXSRA50TlHw==",
      "license": "Apache-2.0",
      "peerDependencies": {
        "zod": "^3.25.0 || ^4.0.0"
      }
    },
    "node_modules/@anthropic-ai/claude-agent-sdk": {
-      "version": "0.3.286",
-      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk/-/claude-agent-sdk-0.3.286.tgz",
-      "integrity": "sha512-InL/UNmRGSwBM/81PME0J0TZDsDBBlweWqRZgq2XSViSIg2hBi8nIL8j9Hm6MHRH85wgDJQE5n6Vo/r9hIO0NQ==",
+      "version": "0.3.287",
+      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk/-/claude-agent-sdk-0.3.287.tgz",
+      "integrity": "sha512-DrYUMzmSVfL1VciNDo/9BhxiVnTsSCKVzxLHB3+NvvRiyN4pfWTKFrUzQesPnWswds9x1Ir10Gi6GRsnjT0UkA==",
      "license": "SEE LICENSE IN README.md",
      "engines": {
        "node": ">=18.0.0"
      },
      "optionalDependencies": {
-        "@anthropic-ai/claude-agent-sdk-darwin-arm64": "0.3.286",
-        "@anthropic-ai/claude-agent-sdk-darwin-x64": "0.3.286",
-        "@anthropic-ai/claude-agent-sdk-linux-arm64": "0.3.286",
-        "@anthropic-ai/claude-agent-sdk-linux-arm64-musl": "0.3.286",
-        "@anthropic-ai/claude-agent-sdk-linux-x64": "0.3.286",
-        "@anthropic-ai/claude-agent-sdk-linux-x64-musl": "0.3.286",
-        "@anthropic-ai/claude-agent-sdk-win32-arm64": "0.3.286",
-        "@anthropic-ai/claude-agent-sdk-win32-x64": "0.3.286"
+        "@anthropic-ai/claude-agent-sdk-darwin-arm64": "0.3.287",
+        "@anthropic-ai/claude-agent-sdk-darwin-x64": "0.3.287",
+        "@anthropic-ai/claude-agent-sdk-linux-arm64": "0.3.287",
+        "@anthropic-ai/claude-agent-sdk-linux-arm64-musl": "0.3.287",
+        "@anthropic-ai/claude-agent-sdk-linux-x64": "0.3.287",
+        "@anthropic-ai/claude-agent-sdk-linux-x64-musl": "0.3.287",
+        "@anthropic-ai/claude-agent-sdk-win32-arm64": "0.3.287",
+        "@anthropic-ai/claude-agent-sdk-win32-x64": "0.3.287"
      },
      "peerDependencies": {
        "@anthropic-ai/sdk": ">=0.93.0",
@@ -72,9 +72,9 @@
      }
    },
    "node_modules/@anthropic-ai/claude-agent-sdk-darwin-arm64": {
-      "version": "0.3.286",
-      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-darwin-arm64/-/claude-agent-sdk-darwin-arm64-0.3.286.tgz",
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+      "version": "0.3.287",
+      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-darwin-arm64/-/claude-agent-sdk-darwin-arm64-0.3.287.tgz",
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      "cpu": [
        "arm64"
      ],
@@ -85,9 +85,9 @@
      ]
    },
    "node_modules/@anthropic-ai/claude-agent-sdk-darwin-x64": {
-      "version": "0.3.286",
-      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-darwin-x64/-/claude-agent-sdk-darwin-x64-0.3.286.tgz",
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+      "version": "0.3.287",
+      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-darwin-x64/-/claude-agent-sdk-darwin-x64-0.3.287.tgz",
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      "cpu": [
        "x64"
      ],
@@ -98,9 +98,9 @@
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    "node_modules/@anthropic-ai/claude-agent-sdk-linux-arm64": {
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      "cpu": [
        "arm64"
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@@ -114,9 +114,9 @@
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    "node_modules/@anthropic-ai/claude-agent-sdk-linux-arm64-musl": {
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-      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-linux-arm64-musl/-/claude-agent-sdk-linux-arm64-musl-0.3.286.tgz",
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+      "version": "0.3.287",
+      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-linux-arm64-musl/-/claude-agent-sdk-linux-arm64-musl-0.3.287.tgz",
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      "cpu": [
        "arm64"
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@@ -130,9 +130,9 @@
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    "node_modules/@anthropic-ai/claude-agent-sdk-linux-x64": {
-      "version": "0.3.286",
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+      "version": "0.3.287",
+      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-linux-x64/-/claude-agent-sdk-linux-x64-0.3.287.tgz",
+      "integrity": "sha512-/6Zw5nym4xfc2eFGaIrS7dt7JoBgASsGUnLWMoPV4M1hGH0tOSPzpixfb4OWO6r9iw9Nn/Zk5Ke1KRuMuja2+Q==",
      "cpu": [
        "x64"
      ],
@@ -146,9 +146,9 @@
      ]
    },
    "node_modules/@anthropic-ai/claude-agent-sdk-linux-x64-musl": {
-      "version": "0.3.286",
-      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-linux-x64-musl/-/claude-agent-sdk-linux-x64-musl-0.3.286.tgz",
-      "integrity": "sha512-WeO/wG2uPh95BhOQi1IsIECdW5gJgC1Q9xtGw4RjV04it1fBMAbUe7aVwP4DQgH8PHnmduA7dRnLtbnZnrGsjg==",
+      "version": "0.3.287",
+      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-linux-x64-musl/-/claude-agent-sdk-linux-x64-musl-0.3.287.tgz",
+      "integrity": "sha512-be7lBO3WihsGbGQbMCAowxmt8vqGgmUo2HkbBee8jrch04LG4LCRj6Ry/gHtYSTle30WAnoyqCLsPHFj064waw==",
      "cpu": [
        "x64"
      ],
@@ -162,9 +162,9 @@
      ]
    },
    "node_modules/@anthropic-ai/claude-agent-sdk-win32-arm64": {
-      "version": "0.3.286",
-      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-win32-arm64/-/claude-agent-sdk-win32-arm64-0.3.286.tgz",
-      "integrity": "sha512-N4p7Gw5Qg3q9+Y5sEht1cIHHZkmBAUfWXJnqfmDD7N8twqF3XNVK3w65hDLqli4i0ttuZu79bGmRGkgNGm9Imw==",
+      "version": "0.3.287",
+      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-win32-arm64/-/claude-agent-sdk-win32-arm64-0.3.287.tgz",
+      "integrity": "sha512-6AdDoLnnVG9aRrWoGVQjS3i4+hceCGFEHVPkMBzbVFs76G1WKlY/ZMnELu3X+ZE5QJFT3j4qqmdJ0y+QbrycEg==",
      "cpu": [
        "arm64"
      ],
@@ -175,9 +175,9 @@
      ]
    },
    "node_modules/@anthropic-ai/claude-agent-sdk-win32-x64": {
-      "version": "0.3.286",
-      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-win32-x64/-/claude-agent-sdk-win32-x64-0.3.286.tgz",
-      "integrity": "sha512-pg35GRPBKyviod0i8Z3EVMzDnTiiiucuWUbyH1bVIFFN0UWCQQ+PRUJ15qrPKjL6+vlFxOX2ei9FfsWYjGYZwA==",
+      "version": "0.3.287",
+      "resolved": "https://registry.npmjs.org/@anthropic-ai/claude-agent-sdk-win32-x64/-/claude-agent-sdk-win32-x64-0.3.287.tgz",
+      "integrity": "sha512-fczDcWG2Hu+nYQgxeQEsGn5l+3M06RpJXysIsu/BmHTPl7UceTfTpSYr6O/9GU/sNhU0CADJaIIZNwQTfK0DWw==",
      "cpu": [
        "x64"
      ],
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
  "publishConfig": {
    "access": "public"
  },
-  "version": "0.85.0",
+  "version": "0.86.0",
  "description": "An ACP-compatible coding agent powered by the Claude Agent SDK (TypeScript)",
  "main": "dist/lib.js",
  "types": "dist/lib.d.ts",
@@ -65,8 +65,8 @@
    "node": ">=22"
  },
  "dependencies": {
-    "@agentclientprotocol/sdk": "1.5.1",
-    "@anthropic-ai/claude-agent-sdk": "0.3.286",
+    "@agentclientprotocol/sdk": "1.7.0",
+    "@anthropic-ai/claude-agent-sdk": "0.3.287",
    "diff": "9.0.0",
    "zod": "4.6.5"
  },
--- a/src/acp-agent.ts
+++ b/src/acp-agent.ts
--- a/src/air-extension.ts
+++ b/src/air-extension.ts
@@ -18,6 +18,8 @@ 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";
 /**
--- 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/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/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-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/tests/acp-agent-settings.test.ts
+++ b/src/tests/acp-agent-settings.test.ts
@@ -399,6 +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/snapshots/air/ask-user-question.jsonl
+++ b/src/tests/acp-scenarios/snapshots/air/ask-user-question.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":"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}}}
--- 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
@@ -1,4 +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":"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}}}}
--- 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"}}}
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--- 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}}
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+{"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"}}}
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+{"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"}}}
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--- 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}}
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+{"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}}}
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+{"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"}}}
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+{"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"}}}
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+{"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"}}}
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--- a/src/tests/acp-scenarios/snapshots/v2/task-create-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/task-create-update.jsonl
@@ -0,0 +1,26 @@
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+{"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"}}}
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+{"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":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"plan":{"entries":[{"content":"Write tests","priority":"medium","status":"pending"}],"planId":"plan","type":"items"},"sessionUpdate":"plan_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"plan":{"entries":[{"content":"Write tests","priority":"medium","status":"pending"}],"planId":"plan","type":"items"},"sessionUpdate":"plan_update"}}}
+{"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":{"plan":{"entries":[{"content":"Write tests","priority":"medium","status":"in_progress"}],"planId":"plan","type":"items"},"sessionUpdate":"plan_update"}}}
+{"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":{"plan":{"entries":[{"content":"Write tests","priority":"medium","status":"completed"}],"planId":"plan","type":"items"},"sessionUpdate":"plan_update"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"plan":{"entries":[{"content":"Write tests","priority":"medium","status":"completed"}],"planId":"plan","type":"items"},"sessionUpdate":"plan_update"}}}
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+{"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}}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 2","type":"text"}],"messageId":"<id-2>","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-2>"}}
+{"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":"All ","type":"text"},"messageId":"msg_follow","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"done.","type":"text"},"messageId":"msg_follow","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/task-output-and-stop.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/task-output-and-stop.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":"TaskOutput"}},"content":[],"kind":"other","name":"TaskOutput","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"TaskOutput","toolCallId":"toolu_out"}}}
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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":"TaskOutput"}},"rawInput":{"block":true,"task_id":"bash_1"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_out"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"TaskOutput"}},"content":[{"content":{"text":"<retrieval_status>success</retrieval_status>\n<output>done</output>","type":"text"},"type":"content"}],"rawOutput":"<retrieval_status>success</retrieval_status>\n<output>done</output>","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_out"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"TaskStop"}},"content":[],"kind":"other","name":"TaskStop","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"TaskStop","toolCallId":"toolu_stop"}}}
+{"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":"TaskStop"}},"rawInput":{"task_id":"bash_1"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_stop"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"TaskStop"}},"content":[{"content":{"text":"Successfully stopped task: bash_1","type":"text"},"type":"content"}],"rawOutput":"Successfully stopped task: bash_1","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_stop"}}}
+{"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/text-and-thinking.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/text-and-thinking.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":{"content":{"text":"Let me thin","type":"text"},"messageId":"msg_text","sessionUpdate":"agent_thought_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"k about it.","type":"text"},"messageId":"msg_text","sessionUpdate":"agent_thought_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"Here is t","type":"text"},"messageId":"msg_text","sessionUpdate":"agent_message_chunk"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"he answer.","type":"text"},"messageId":"msg_text","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/todo-write.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/todo-write.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":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"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":{"plan":{"entries":[{"content":"Writing tests","priority":"medium","status":"in_progress"},{"content":"Ship","priority":"medium","status":"pending"}],"planId":"plan","type":"items"},"sessionUpdate":"plan_update"}}}
+{"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/tool-progress.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/tool-progress.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":{"sessionUpdate":"terminal_update","terminalId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"content":[{"terminalId":"toolu_slow","type":"terminal"}],"kind":"execute","name":"Bash","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Terminal","toolCallId":"toolu_slow"}}}
+{"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":"make","sessionUpdate":"terminal_update","terminalId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"rawInput":{"command":"make"},"sessionUpdate":"tool_call_update","title":"make","toolCallId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash","toolResponse":{"elapsedTimeSeconds":1}}},"sessionUpdate":"tool_call_update","status":"in_progress","toolCallId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash","toolResponse":{"elapsedTimeSeconds":2}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash","toolResponse":{"elapsedTimeSeconds":3}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"output":{"data":"YnVpbHQ="},"sessionUpdate":"terminal_update","terminalId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"exitStatus":{"exitCode":0},"sessionUpdate":"terminal_update","terminalId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Bash"}},"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_slow"}}}
+{"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/web-fetch-and-search.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/web-fetch-and-search.jsonl
@@ -0,0 +1,21 @@
+{"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":"WebFetch"}},"content":[],"kind":"fetch","name":"WebFetch","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Fetch","toolCallId":"toolu_fetch"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"WebFetch"}},"rawInput":{"url":"https://example.com"},"sessionUpdate":"tool_call_update","title":"Fetch https://example.com","toolCallId":"toolu_fetch"}}}
+{"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":"WebFetch"}},"content":[{"content":{"text":"Summarize the page","type":"text"},"type":"content"}],"rawInput":{"prompt":"Summarize the page","url":"https://example.com"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_fetch"}}}
+{"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":"allow_always","name":"Yes, and don't ask again for example.com","optionId":"allow-with-updates"},{"kind":"reject_once","name":"No","optionId":"reject"}],"sessionId":"<session>","subject":{"toolCall":{"content":[{"content":{"text":"Summarize the page","type":"text"},"type":"content"}],"kind":"fetch","name":"WebFetch","rawInput":{"prompt":"Summarize the page","url":"https://example.com"},"status":"pending","title":"Fetch https://example.com","toolCallId":"toolu_fetch"},"type":"tool_call"},"title":"Fetch https://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":{"claudeCode":{"toolName":"WebFetch"}},"content":[{"content":{"text":"The page is an example.","type":"text"},"type":"content"}],"rawOutput":"The page is an example.","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_fetch"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"WebSearch"}},"content":[],"kind":"fetch","name":"WebSearch","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Web search","toolCallId":"toolu_search"}}}
+{"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":"WebSearch"}},"rawInput":{"query":"acp protocol"},"sessionUpdate":"tool_call_update","title":"Search \"acp protocol\"","toolCallId":"toolu_search"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"WebSearch"}},"content":[{"content":{"text":"ACP (https://agentclientprotocol.com)\nA summary.","type":"text"},"type":"content"}],"rawOutput":"Web search results for query: \"acp protocol\"\n\nLinks: [...]","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_search"}}}
+{"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/write-existing.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/write-existing.jsonl
@@ -0,0 +1,15 @@
+{"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":"Write"}},"content":[],"kind":"edit","locations":[],"name":"Write","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Preparing file…","toolCallId":"toolu_write"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Write"}},"locations":[{"path":"<cwd>/old.ts"}],"rawInput":{"file_path":"<cwd>/old.ts"},"sessionUpdate":"tool_call_update","title":"Write old.ts","toolCallId":"toolu_write"}}}
+{"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":"Write"}},"rawInput":{"content":"export const x = 1;\n","file_path":"<cwd>/old.ts"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_write"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Write"}},"rawOutput":"The file <cwd>/old.ts has been updated successfully.","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_write"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Write","toolResponse":{"content":"export const x = 1;\n","filePath":"<cwd>/old.ts","originalFile":"export const x = 0;\n","structuredPatch":[{"lines":["-export const x = 0;","+export const x = 1;"],"newLines":1,"newStart":1,"oldLines":1,"oldStart":1}],"type":"update"}}},"content":[{"changes":[{"fileType":"text","operation":"modify","path":"<cwd>/old.ts"}],"patch":{"format":"git_patch","text":"diff --git <cwd>/old.ts <cwd>/old.ts\n--- <cwd>/old.ts\n+++ <cwd>/old.ts\n@@ -1 +1 @@\n-export const x = 0;\n+export const x = 1;\n"},"type":"diff"}],"locations":[{"line":1,"path":"<cwd>/old.ts"}],"sessionUpdate":"tool_call_update","toolCallId":"toolu_write"}}}
+{"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