fix: display active Central helpers as JetBrains Air Gateway (#1266 )

### Summary Addresses [IJAI-2956](https://youtrack.jetbrains.com/issue/IJAI-2956). - Recognize Central only when the active key source is `apiKeyHelper` and its effective helper command contains the whole word `central` and the word sequence `proxy start`, case-insensitively, allowing multiple whitespace characters. - Read the effective command through the existing `SettingsManager`/SDK settings resolution, including project/managed overrides, rather than reimplementing configuration merging or executing helpers. - Return `kind: gateway` and the exact label `JetBrains Air Gateway`, without `detail` or invented account identity. URL, flags, routes, and endpoint ownership are intentionally not checked: this is an agreed weak display heuristic, not proof of provenance or entitlement. - Render ordinary helpers as `API key helper` instead of raw `apiKeyHelper`; do not expose unknown key-source identifiers. Preserve external backend and client-owned configuration priority, CLI/SDK merging, stale-probe protection, and duplicate suppression. - Add mapper and ACP-agent regression coverage for positive/negative commands, overrides, CLI/SDK results, and source changes; update `docs/air-extensions.md`. Examples matching the heuristic include `central proxy start` and `/opt/bin/CeNtRaL PrOxY StArT --arbitrary-flag`. `decentralized proxy start`, `central start`, and an inactive helper do not match. ### Sanitized auth status ```json { "kind": "gateway", "label": "JetBrains Air Gateway" } ``` No helper command, key, header, private route, or invented account information is sent. ### Verification Based on fresh upstream `main` at `0724b17`, rechecked immediately before publication. Changes and rebuilt `dist` are available in the main local clone; the user confirmed the local adapters work. ```bash npm run build npm run lint npm run test:run ``` - Build and lint passed. - Full test suite: **2484 passed, 30 existing skipped** across 44 passed test files and 4 skipped files. - No new skip flags or disabled tests were used. ### Scope No AIR UI, provisioning, personal configuration migration, effort/mode changes, or new ACP protocol. Plan files and personal configurations are not committed. --------- Co-authored-by: Junie <junie@jetbrains.com> Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com> Co-authored-by: Andrey Bragin <andrey.bragin@jetbrains.com>
refactor: send each tool call's _meta as the state a v2 client stores on the experimental ACP v2 surface (#1318 )
2026-10-27 12:40:32 +00:00 · 2026-10-13 14:29:48 +02:00 · 2026-10-13 07:57:05 +02:00 · 2026-10-13 05:28:48 +00:00 · 2026-10-13 07:13:50 +02:00 · 2026-10-12 22:18:38 +02:00
67 changed files with 5456 additions and 586 deletions
--- a/docs/air-extensions.md
+++ b/docs/air-extensions.md
@@ -17,6 +17,7 @@ It describes only this adapter.
 - [Claude tools and ACP fields](#claude-tools-and-acp-fields)
 - [Diff patch](#diff-patch)
 - [Plan file](#plan-file)
+- [Session hooks](#session-hooks)
 - [Permission presentation](#permission-presentation)
 - [Goal](#goal)
 - [Recommended config values](#recommended-config-values)
@@ -205,6 +206,20 @@ The adapter keeps them where they are.
 | `quota`                 | `PromptResponse._meta.quota`                                                                                                              | Token usage of the turn, also split by model.                                      |
 | `authStatus`            | `initialize` response `agentCapabilities._meta.authStatus`                                                                                | The agent pushes `_auth/status_update`. The object carries no payload.             |

+## Auth source display
+
+The connection-scoped `_auth/status_update` continues to report agent-owned authentication, not client-owned `providers/set` routing. When the active key source is `apiKeyHelper`, the adapter reads the effective helper command through SDK `resolveSettings` / the session's `SettingsManager`, including programmatic settings overrides.
+
+A command containing the whole word `central` and the word sequence `proxy start` is displayed as:
+
+```json
+{ "authStatus": { "kind": "gateway", "label": "JetBrains Air Gateway" } }
+```
+
+Matching is case-insensitive and accepts multiple whitespace characters between `proxy` and `start`. The command's flags, URL, host and route are not checked. This is a weak display heuristic, not proof of configuration provenance, account ownership or entitlement. Inactive helpers and external cloud backends retain their existing classification. No helper command, key, headers, private route or inferred account is included in this payload.
+
+Other active helpers use `label: "Anthropic API key"` and `detail: "API key helper"`; unknown key-source identifiers are not exposed as display text. CLI and SDK reads share this presentation, retain stale-probe protection, and suppress unchanged notifications.
+
 ## Zed conventions

 The adapter keeps these Zed and upstream conventions unchanged for every client.
@@ -496,6 +511,21 @@ The plan text goes out as before in these cases:
 AIR then shows the in-memory `plan` text.
 A client that is not AIR always gets the whole SDK input, like upstream.

+## Session hooks
+
+The adapter accepts session hooks from any client, without a capability.
+AIR puts the hooks into `_meta.claudeCode.options.settings.hooks` of `session/new` and `session/load`:
+
+```json
+{ "claudeCode": { "options": { "settings": { "hooks": { "Stop": [{ "hooks": [{ "type": "command", "command": "..." }] }] } } } }
+```
+
+- The settings go to the flag settings tier of that session only. Other sessions and the settings files do not change.
+- Claude Code runs the hooks of every settings tier, so the user, project and IDE hooks of one event all run. `src/tests/session-hooks.test.ts` checks this with the Claude Code binary.
+- `CLAUDE_MODEL_CONFIG` stays in effect (see [Model configuration](model-configuration.md#precedence)).
+- A `session/load` with different settings recreates the query, so it applies the new hooks.
+- Claude asks for no hook trust step.
+
 ## Permission presentation

 The adapter uses standard ACP permission requests and responses.
@@ -1525,6 +1555,8 @@ It adds this object to the `session/fork` request:
  When only one stored message has the fingerprint, the adapter uses that message.
 - When no message matches, the request fails with `invalidParams`.
 - The fork keeps the history up to that message.
+- With or without this object, the forked session runs once the response arrives, so the client can prompt it without `session/load` or `session/resume`.
+  A later load replays its history into it, and a later resume returns it. A load or resume with other settings (`cwd`, MCP servers, additional directories, or the session options in `_meta`) restarts it, as for any loaded session.

 ## Presentation hints

--- a/docs/model-configuration.md
+++ b/docs/model-configuration.md
@@ -42,12 +42,12 @@ node dist/index.js

 ## Precedence

-When an ACP caller provides `settings` via `_meta.claudeCode.options.settings` in the `sessions/create` request, `CLAUDE_MODEL_CONFIG` is ignored entirely. The env var is a deployment-level fallback for cases where the caller does not configure model settings itself.
+An ACP caller can provide `settings` via `_meta.claudeCode.options.settings` in `session/new` or `session/load`, as an object or a path to a settings file. The adapter merges `CLAUDE_MODEL_CONFIG` into those settings, so a caller that only adds hooks keeps the model settings. When both set the same key, the caller wins; the merge is shallow, so a caller's `modelOverrides` replaces the env var's map.

-| Source                                       | Priority                                              |
-| -------------------------------------------- | ----------------------------------------------------- |
-| `_meta.claudeCode.options.settings` (caller) | Highest — used if present                             |
-| `CLAUDE_MODEL_CONFIG` (env var)              | Fallback — used only when caller provides no settings |
+| Source                                       | Priority                                       |
+| -------------------------------------------- | ---------------------------------------------- |
+| `_meta.claudeCode.options.settings` (caller) | Highest — wins for each key it sets            |
+| `CLAUDE_MODEL_CONFIG` (env var)              | Used for the keys that the caller does not set |

 ## Format details

--- a/src/acp-agent.ts
+++ b/src/acp-agent.ts
--- a/src/async-tasks.ts
+++ b/src/async-tasks.ts
@@ -786,7 +786,7 @@ export function backgroundBashTaskFromToolResult(
  content: unknown,
  toolUseResult: unknown,
  toolUses: Record<string, { name: string; input: unknown }>,
-): AsyncTaskStarted | undefined {
+): (AsyncTaskStarted & { taskId: string; toolCallId: string }) | undefined {
  if (!Array.isArray(content)) return undefined;
  const toolResults = content.flatMap(toolResultBlock);
  const bashResults = toolResults.filter((result) => toolUses[result.toolUseId]?.name === "Bash");
--- a/src/auth-status.ts
+++ b/src/auth-status.ts
@@ -103,6 +103,13 @@ const NOT_LOGGED_IN: AuthStatus = {
  label: "Not logged in",
 };

+const API_KEY_SOURCE_DETAILS = new Map([
+  ["apiKeyHelper", "API key helper"],
+  ["env", "env"],
+  ["ANTHROPIC_API_KEY", "ANTHROPIC_API_KEY"],
+  ["ANTHROPIC_AUTH_TOKEN", "ANTHROPIC_AUTH_TOKEN"],
+]);
+
 /** Display names for the non-firstParty backends, where auth lives outside the
 *  agent (AWS credentials, gcloud ADC, …). */
 const EXTERNAL_PROVIDER_LABELS: Record<string, string> = {
@@ -162,7 +169,10 @@ export function accountInfoHasIdentitySignal(account: AccountInfo | undefined):
 /** Session-time mapping from the SDK's `AccountInfo`, the richest source when
 *  it is populated. Returns `undefined` when the account carries no identity
 *  signal, so callers keep the status they already know. */
-export function fromAccountInfo(account: AccountInfo | undefined): AuthStatus | undefined {
+export function fromAccountInfo(
+  account: AccountInfo | undefined,
+  apiKeyHelper?: string,
+): AuthStatus | undefined {
  if (!account || !accountInfoHasIdentitySignal(account)) {
    return undefined;
  }
@@ -172,13 +182,14 @@ export function fromAccountInfo(account: AccountInfo | undefined): AuthStatus |
    apiKeySource: account.apiKeySource,
    email: account.email,
    organization: account.organization,
+    apiKeyHelper,
  });
 }

 /** Pre-session mapping from `claude auth status --json` stdout. Returns
 *  `undefined` when the output is not the expected JSON object, so callers can
 *  report "not known" instead of guessing. */
-export function fromCliStatus(stdout: string): AuthStatus | undefined {
+export function fromCliStatus(stdout: string, apiKeyHelper?: string): AuthStatus | undefined {
  let parsed: unknown;
  try {
    parsed = JSON.parse(stdout);
@@ -205,6 +216,7 @@ export function fromCliStatus(stdout: string): AuthStatus | undefined {
    apiKeySource: status.apiKeySource,
    email: status.email,
    organization: status.orgName,
+    apiKeyHelper,
  });
 }

@@ -224,6 +236,7 @@ function mapAuthFields(fields: {
  apiKeySource?: string;
  email?: string;
  organization?: string;
+  apiKeyHelper?: string;
 }): AuthStatus {
  const { apiProvider, subscriptionType, apiKeySource, email, organization } = fields;

@@ -237,11 +250,19 @@ function mapAuthFields(fields: {
    };
  }
  if (apiKeySource) {
+    if (
+      apiKeySource === "apiKeyHelper" &&
+      typeof fields.apiKeyHelper === "string" &&
+      /\bcentral\b/i.test(fields.apiKeyHelper) &&
+      /\bproxy\s+start\b/i.test(fields.apiKeyHelper)
+    ) {
+      return { kind: "gateway", label: "JetBrains Air Gateway" };
+    }
+    const detail = API_KEY_SOURCE_DETAILS.get(apiKeySource);
    return {
      kind: "api_key",
      label: "Anthropic API key",
-      // The source ("apiKeyHelper", "env", …) is the specifics line.
-      detail: apiKeySource,
+      ...(detail ? { detail } : {}),
    };
  }
  if (subscriptionType) {
--- a/src/exit-plan.ts
+++ b/src/exit-plan.ts
@@ -126,6 +126,38 @@ export function isExitPlanInterruptionResult(
  );
 }

+/** The id of the plan that an approved ExitPlanMode publishes. Claude Code
+ * keeps one plan file per session, which a later plan mode rewrites, so each
+ * approval replaces the plan before it. The TodoWrite checklist is a
+ * separate plan. */
+export const PLAN_MODE_PLAN_ID = "plan-mode";
+
+/** The plan, trimmed, that a successful ExitPlanMode result approved: the plan
+ * of the structured `output`, which includes the user's edits, else the plan
+ * that Claude Code adds to the tool's `input`. Replay has only the input: the
+ * SDK's `getSessionMessages` drops the structured output that the transcript
+ * keeps. Undefined for a subagent's plan, one that waits for its team lead
+ * (both only known from the output), and an empty plan. */
+export function approvedPlan(input: unknown, output: unknown): string | undefined {
+  const result = output as
+    { plan?: unknown; isAgent?: unknown; awaitingLeaderApproval?: unknown } | undefined;
+  if (result?.isAgent === true || result?.awaitingLeaderApproval === true) return undefined;
+  const plan =
+    typeof result?.plan === "string"
+      ? result.plan
+      : (input as { plan?: unknown } | undefined)?.plan;
+  return typeof plan === "string" && plan.trim() !== "" ? plan.trim() : undefined;
+}
+
+/** The update that shows an approved plan to a client that supports plan
+ * operations (the `plan` client capability, which every v2 client has). */
+export function planModeUpdate(plan: string): SessionNotification["update"] {
+  return {
+    sessionUpdate: "plan_update",
+    plan: { type: "markdown", planId: PLAN_MODE_PLAN_ID, content: plan },
+  };
+}
+
 /** Claude wraps a rejected ExitPlanMode explanation in a Markdown code fence.
 * Strip exactly one complete outer fence for that tool only. */
 export function exitPlanModeRawOutput(toolName: string, content: unknown): unknown {
@@ -144,6 +176,8 @@ export type ExitPlanRestartHost<
  "publishSessionState" | "continuationMessage"
 > & {
  sessionUpdate(notification: SessionNotification): Promise<void>;
+  /** Whether the client takes plan operations (see planModeUpdate). */
+  supportsPlanOperations(): boolean;
  destroyReplacement(sessionId: string, session: Session): void;
  settleCancelledTurn(oldSession: Session, turnSession: Session, turn: Turn): void;
  settleFailedTurn(turnSession: Session, turn: Turn, error: unknown): void;
@@ -180,6 +214,12 @@ export class ExitPlanCoordinator<
            sessionId: id,
            update: { sessionUpdate: "config_option_update", configOptions },
          });
+          // The approved plan becomes the session's plan once the fresh
+          // context that carries it out exists. Its ExitPlanMode ended with
+          // an error result, so toAcpNotifications did not publish it.
+          if (this.host.supportsPlanOperations()) {
+            await this.host.sessionUpdate({ sessionId: id, update: planModeUpdate(reset.plan) });
+          }
        },
        continuationMessage: (id, plan, promptUuid) => ({
          type: "user",
--- a/src/settings.ts
+++ b/src/settings.ts
@@ -50,6 +50,7 @@ export class SettingsManager {
  private cwd: string;
  private effective: Settings = {};
  private managedDeniedModels: string[] = [];
+  private managedApiKeyHelper?: string;
  private watchers: fs.FSWatcher[] = [];
  private onChange?: () => void;
  private logger: { log: (...args: any[]) => void; error: (...args: any[]) => void };
@@ -111,10 +112,15 @@ export class SettingsManager {
      this.managedDeniedModels = resolved.sources
        .filter((entry) => entry.source === "managed")
        .flatMap((entry) => entry.settings.deniedModels ?? []);
+      this.managedApiKeyHelper =
+        resolved.provenance.apiKeyHelper?.source === "managed"
+          ? resolved.effective.apiKeyHelper
+          : undefined;
    } catch (error) {
      this.logger.error("Failed to resolve settings:", error);
      this.effective = {};
      this.managedDeniedModels = [];
+      this.managedApiKeyHelper = undefined;
    }
  }

@@ -177,6 +183,16 @@ export class SettingsManager {
    return this.effective;
  }

+  /**
+   * The `apiKeyHelper` the CLI runs: managed settings outrank the `--settings`
+   * override, which outranks the user/project/local files.
+   */
+  getApiKeyHelper(settingsOverride?: Settings): string | undefined {
+    return (
+      this.managedApiKeyHelper ?? settingsOverride?.apiKeyHelper ?? this.effective.apiKeyHelper
+    );
+  }
+
  /**
   * `deniedModels` entries from the managed tier, the only tier the CLI
   * honors them from.
--- a/src/tests/acp-agent.test.ts
+++ b/src/tests/acp-agent.test.ts
--- a/src/tests/acp-scenarios/snapshots/v2/ask-user-question.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/ask-user-question.jsonl
@@ -1,15 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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
@@ -1,6 +1,6 @@
 {"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":{"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"}],"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":{"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":{"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/async-task-held-until-tool-id.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/async-task-held-until-tool-id.jsonl
@@ -1,6 +1,6 @@
 {"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":{"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"}],"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":{"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":{"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/async-task-released-at-turn-end.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/async-task-released-at-turn-end.jsonl
@@ -1,6 +1,6 @@
 {"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":{"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"}],"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":{"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":{"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/bash-background.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/bash-background.jsonl
@@ -1,18 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"rawInput":{"command":"sleep 100"},"sessionUpdate":"tool_call_update","title":"sleep 100","toolCallId":"toolu_bg"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"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":{"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
@@ -1,17 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"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
@@ -1,22 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"sessionUpdate":"tool_call_update","status":"completed","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}}}
--- a/src/tests/acp-scenarios/snapshots/v2/compaction-failed-legacy.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/compaction-failed-legacy.jsonl
@@ -1,8 +1,8 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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
@@ -1,8 +1,8 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/compaction-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/compaction-update.jsonl
@@ -1,8 +1,8 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/edit-rejected.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/edit-rejected.jsonl
@@ -1,18 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"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":{"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"}],"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":{"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
@@ -1,19 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"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":{"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"}],"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":{"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":{"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
@@ -1,16 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"plan":{"content":"# Plan\n1. Do it","planId":"plan-mode","type":"markdown"},"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/exit-plan-reject.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/exit-plan-reject.jsonl
@@ -1,15 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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
@@ -1,6 +1,6 @@
 {"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":{"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"}],"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":{"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":{"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/grep-and-glob.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/grep-and-glob.jsonl
@@ -1,19 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"rawInput":{"pattern":"value"},"sessionUpdate":"tool_call_update","title":"grep \"value\"","toolCallId":"toolu_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"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":{"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":{"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":{"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":{"rawInput":{"pattern":"**/*.ts"},"sessionUpdate":"tool_call_update","title":"Find `**/*.ts`","toolCallId":"toolu_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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
@@ -1,16 +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":{"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"}],"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":{"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"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"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"}}},"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":{"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":{"_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
@@ -1,8 +1,8 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolResponse":{"mode":"select"}}},"kind":"read","locations":[{"path":"/memory/a.md"},{"path":"/memory/b.md"}],"name":"memory_recall","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":{"toolResponse":{"mode":"synthesize"}}},"content":[{"content":{"text":"The user prefers tabs.","type":"text"},"type":"content"}],"kind":"read","name":"memory_recall","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
@@ -1,9 +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":{"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"}],"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":{"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":"running"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/notebook-edit.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/notebook-edit.jsonl
@@ -1,18 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"rawInput":{"notebook_path":"<cwd>/n.ipynb"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_nb"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"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":{"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":{"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
@@ -1,17 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"toolResponse":{"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":{"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
@@ -1,8 +1,8 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/read.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/read.jsonl
@@ -1,13 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"_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
@@ -6,14 +6,14 @@
 {"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":{"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":{"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":{"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":[{"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":{"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":{"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":{"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"}],"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"}]}}
--- a/src/tests/acp-scenarios/snapshots/v2/skill.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/skill.jsonl
@@ -1,13 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"rawInput":{"skill":"commits"},"sessionUpdate":"tool_call_update","title":"Load skill: commits","toolCallId":"toolu_skill"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawOutput":"Launching skill: commits","sessionUpdate":"tool_call_update","status":"completed","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
@@ -1,17 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"rawInput":{"description":"Background review"},"sessionUpdate":"tool_call_update","title":"Background review","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"description":"Background review","prompt":"Review the diff"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_agent"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"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":{"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":{"toolResponse":{"isAsync":true,"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}}}
--- a/src/tests/acp-scenarios/snapshots/v2/subagent-late-child-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/subagent-late-child-update.jsonl
@@ -1,18 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"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"}},"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":{"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":{"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":{"parentToolUseId":"toolu_late","toolResponse":{"elapsedTimeSeconds":4}}},"sessionUpdate":"tool_call_update","status":"in_progress","toolCallId":"toolu_late_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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
@@ -1,31 +1,31 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"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":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native"}},"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":{"rawInput":{"pattern":"TODO"},"sessionUpdate":"tool_call_update","title":"grep \"TODO\"","toolCallId":"toolu_native_grep"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"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":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_native"}},"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":{"rawInput":{"command":"make"},"sessionUpdate":"tool_call_update","title":"make","toolCallId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":"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"}},"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":{"sessionUpdate":"tool_call_update","status":"failed","toolCallId":"toolu_native_bash"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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
@@ -1,24 +1,24 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[],"kind":"think","name":"Agent","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_outer"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Plan the work"},"sessionUpdate":"tool_call_update","title":"Plan the work","toolCallId":"toolu_outer"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"rawInput":{"description":"Plan the work","prompt":"Plan it"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_outer"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"kind":"think","name":"Agent","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_outer"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"description":"Plan the work"},"sessionUpdate":"tool_call_update","title":"Plan the work","toolCallId":"toolu_outer"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"description":"Plan the work","prompt":"Plan it"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_outer"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"Plan it","type":"text"},"type":"content"}],"rawInput":{"description":"Plan the work","prompt":"Plan it","subagent_type":"Plan"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_outer"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer","toolName":"Agent"}},"content":[],"kind":"think","name":"Agent","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_inner"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer","toolName":"Agent"}},"rawInput":{"description":"Read the spec"},"sessionUpdate":"tool_call_update","title":"Read the spec","toolCallId":"toolu_inner"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer","toolName":"Agent"}},"rawInput":{"description":"Read the spec","prompt":"Read spec.md"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_inner"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer","toolName":"Agent"}},"content":[{"content":{"text":"Read spec.md","type":"text"},"type":"content"}],"rawInput":{"description":"Read the spec","prompt":"Read spec.md","subagent_type":"Explore"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_inner"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_inner","toolName":"Read"}},"content":[],"kind":"read","locations":[],"name":"Read","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Read File","toolCallId":"toolu_grandchild_read"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_inner","toolName":"Read"}},"locations":[{"line":1,"path":"/spec.md"}],"rawInput":{"file_path":"/spec.md"},"sessionUpdate":"tool_call_update","title":"Read /spec.md","toolCallId":"toolu_grandchild_read"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_inner","toolName":"Read"}},"content":[{"content":{"text":"```\n1\tspec\n```","type":"text"},"type":"content"}],"rawOutput":"1\tspec","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_grandchild_read"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer","toolName":"Agent"}},"content":[{"content":{"text":"The spec says X.","type":"text"},"type":"content"}],"rawOutput":[{"text":"The spec says X.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_inner"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"Plan it","type":"text"},"type":"content"}],"rawInput":{"description":"Plan the work","prompt":"Plan it","subagent_type":"Plan"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_outer"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer"}},"content":[],"kind":"think","name":"Agent","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_inner"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"description":"Read the spec"},"sessionUpdate":"tool_call_update","title":"Read the spec","toolCallId":"toolu_inner"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"description":"Read the spec","prompt":"Read spec.md"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_inner"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"Read spec.md","type":"text"},"type":"content"}],"rawInput":{"description":"Read the spec","prompt":"Read spec.md","subagent_type":"Explore"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_inner"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_inner"}},"content":[],"kind":"read","locations":[],"name":"Read","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Read File","toolCallId":"toolu_grandchild_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"locations":[{"line":1,"path":"/spec.md"}],"rawInput":{"file_path":"/spec.md"},"sessionUpdate":"tool_call_update","title":"Read /spec.md","toolCallId":"toolu_grandchild_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"```\n1\tspec\n```","type":"text"},"type":"content"}],"rawOutput":"1\tspec","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_grandchild_read"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"The spec says X.","type":"text"},"type":"content"}],"rawOutput":[{"text":"The spec says X.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_inner"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer"}},"content":{"text":"Plan:","type":"text"},"messageId":"msg_outer_text","sessionUpdate":"agent_message_chunk"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_outer"}},"content":{"text":" do X.","type":"text"},"messageId":"msg_outer_text","sessionUpdate":"agent_message_chunk"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Agent"}},"content":[{"content":{"text":"Plan: do X.","type":"text"},"type":"content"}],"rawOutput":[{"text":"Plan: do X.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_outer"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"Plan: do X.","type":"text"},"type":"content"}],"rawOutput":[{"text":"Plan: do X.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_outer"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/subagent-task-legacy.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/subagent-task-legacy.jsonl
@@ -1,43 +1,43 @@
 {"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":{"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"}],"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":{"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>"}}
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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":"terminal_update","terminalId":"toolu_sub_bash"}}}
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 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"command":"rg parser","sessionUpdate":"terminal_update","terminalId":"toolu_sub_bash"}}}
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+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_sub_bash"}}}
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-{"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":{"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":{"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"}}}
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+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"The parser is in x.ts.","type":"text"},"type":"content"}],"rawOutput":[{"text":"The parser is in x.ts.\nagentId: a1 (use SendMessage to continue)","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_task"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolResponse":{"status":"completed"}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_task"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
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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
@@ -1,21 +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}}
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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":{"sessionUpdate":"state_update","state":"running"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[],"kind":"think","name":"Task","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_transcript"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"rawInput":{"description":"Summarize"},"sessionUpdate":"tool_call_update","title":"Summarize","toolCallId":"toolu_transcript"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"rawInput":{"description":"Summarize","prompt":"Summarize the repo"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"kind":"think","name":"Task","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Task","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"description":"Summarize"},"sessionUpdate":"tool_call_update","title":"Summarize","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"description":"Summarize","prompt":"Summarize the repo"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_transcript"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"sessionUpdate":"usage_update","size":200000,"used":3}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[{"content":{"text":"Summarize the repo","type":"text"},"type":"content"}],"rawInput":{"description":"Summarize","prompt":"Summarize the repo","subagent_type":"Explore"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"Summarize the repo","type":"text"},"type":"content"}],"rawInput":{"description":"Summarize","prompt":"Summarize the repo","subagent_type":"Explore"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_transcript"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript"}},"content":{"text":"Look at t","type":"text"},"messageId":"msg_transcript_sub","sessionUpdate":"agent_thought_chunk"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript"}},"content":{"text":"he layout.","type":"text"},"messageId":"msg_transcript_sub","sessionUpdate":"agent_thought_chunk"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript"}},"content":{"text":"The repo has ","type":"text"},"messageId":"msg_transcript_sub","sessionUpdate":"agent_message_chunk"}}}
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-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript","toolName":"Glob"}},"content":[],"kind":"search","locations":[],"name":"Glob","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Find","toolCallId":"toolu_transcript_glob"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript","toolName":"Glob"}},"rawInput":{"pattern":"*"},"sessionUpdate":"tool_call_update","title":"Find `*`","toolCallId":"toolu_transcript_glob"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript","toolName":"Glob"}},"content":[{"content":{"text":"a\nb","type":"text"},"type":"content"}],"rawOutput":"a\nb","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_transcript_glob"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"Task"}},"content":[{"content":{"text":"Two packages.","type":"text"},"type":"content"}],"rawOutput":[{"text":"Two packages.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_transcript"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"parentToolUseId":"toolu_transcript"}},"content":[],"kind":"search","locations":[],"name":"Glob","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"Find","toolCallId":"toolu_transcript_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"pattern":"*"},"sessionUpdate":"tool_call_update","title":"Find `*`","toolCallId":"toolu_transcript_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"a\nb","type":"text"},"type":"content"}],"rawOutput":"a\nb","sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_transcript_glob"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"content":{"text":"Two packages.","type":"text"},"type":"content"}],"rawOutput":[{"text":"Two packages.","type":"text"}],"sessionUpdate":"tool_call_update","status":"completed","toolCallId":"toolu_transcript"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"_claude/model":"claude-sonnet-4-6"},"cost":{"amount":0,"currency":"USD"},"sessionUpdate":"usage_update","size":200000,"used":2}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"quota":{"model_usage":[],"token_count":{"cachedInputTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"reasoningOutputTokens":0,"totalTokens":0}}},"sessionUpdate":"state_update","state":"idle","stopReason":"end_turn","usage":{"cachedReadTokens":0,"cachedWriteTokens":0,"inputTokens":0,"outputTokens":0,"totalTokens":0}}}}
--- a/src/tests/acp-scenarios/snapshots/v2/task-create-update.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/task-create-update.jsonl
@@ -1,8 +1,8 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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"}}}
@@ -15,8 +15,8 @@
 {"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}}}}
 {"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/task-output-and-stop.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/task-output-and-stop.jsonl
@@ -1,17 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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"}}}
-{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolName":"TaskOutput"}},"rawInput":{"task_id":"bash_1"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_out"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"kind":"other","name":"TaskOutput","rawInput":{},"sessionUpdate":"tool_call_update","status":"pending","title":"TaskOutput","toolCallId":"toolu_out"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"task_id":"bash_1"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_out"}}}
 {"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":{"rawInput":{"block":true,"task_id":"bash_1"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_out"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"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":{"rawInput":{"task_id":"bash_1"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_stop"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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
@@ -1,8 +1,8 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/todo-write.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/todo-write.jsonl
@@ -1,8 +1,8 @@
 {"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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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"}}}
--- a/src/tests/acp-scenarios/snapshots/v2/tool-progress.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/tool-progress.jsonl
@@ -1,19 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"rawInput":{"command":"make"},"sessionUpdate":"tool_call_update","title":"make","toolCallId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolResponse":{"elapsedTimeSeconds":1}}},"sessionUpdate":"tool_call_update","status":"in_progress","toolCallId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"toolResponse":{"elapsedTimeSeconds":2}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_slow"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"_meta":{"claudeCode":{"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":{"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
@@ -1,20 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"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":{"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":{"rawInput":{"query":"acp protocol"},"sessionUpdate":"tool_call_update","title":"Search \"acp protocol\"","toolCallId":"toolu_search"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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
@@ -1,15 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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":{"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":{"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":{"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":{"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"}],"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"}}},"locations":[{"line":1,"path":"<cwd>/old.ts"}],"sessionUpdate":"tool_call_update","toolCallId":"toolu_write"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"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/src/tests/acp-scenarios/snapshots/v2/write-new.jsonl
+++ b/src/tests/acp-scenarios/snapshots/v2/write-new.jsonl
@@ -1,18 +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":{"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"}],"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":{"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":{"sessionUpdate":"state_update","state":"running"}}}
 {"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>/new.ts"}],"rawInput":{"file_path":"<cwd>/new.ts"},"sessionUpdate":"tool_call_update","title":"Write new.ts","toolCallId":"toolu_write"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"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":{"locations":[{"path":"<cwd>/new.ts"}],"rawInput":{"file_path":"<cwd>/new.ts"},"sessionUpdate":"tool_call_update","title":"Write new.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>/new.ts"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_write"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawInput":{"content":"export const x = 1;\n","file_path":"<cwd>/new.ts"},"sessionUpdate":"tool_call_update","toolCallId":"toolu_write"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"changes":[{"fileType":"text","operation":"add","path":"<cwd>/new.ts"}],"patch":{"format":"git_patch","text":"diff --git <cwd>/new.ts <cwd>/new.ts\nnew file mode 100644\n--- /dev/null\n+++ <cwd>/new.ts\n@@ -0,0 +1 @@\n+export const x = 1;\n"},"type":"diff"}],"sessionUpdate":"tool_call_update","toolCallId":"toolu_write"}}}
 {"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":"add","path":"<cwd>/new.ts"}],"patch":{"format":"git_patch","text":"diff --git <cwd>/new.ts <cwd>/new.ts\nnew file mode 100644\n--- /dev/null\n+++ <cwd>/new.ts\n@@ -0,0 +1 @@\n+export const x = 1;\n"},"type":"diff"}],"kind":"edit","locations":[{"path":"<cwd>/new.ts"}],"name":"Write","rawInput":{"content":"export const x = 1;\n","file_path":"<cwd>/new.ts"},"status":"pending","title":"Write new.ts","toolCallId":"toolu_write"},"type":"tool_call"},"title":"Write new.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":"Write"}},"rawOutput":"File created successfully at: <cwd>/new.ts","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>/new.ts","originalFile":null,"structuredPatch":[],"type":"create"}}},"sessionUpdate":"tool_call_update","toolCallId":"toolu_write"}}}
+{"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"rawOutput":"File created successfully at: <cwd>/new.ts","sessionUpdate":"tool_call_update","status":"completed","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/src/tests/acp-v2.test.ts
+++ b/src/tests/acp-v2.test.ts
--- a/src/tests/auth-status.test.ts
+++ b/src/tests/auth-status.test.ts
@@ -6,6 +6,9 @@ import type { AuthStatus } from "../auth-status.js";
 import { fromAccountInfo, fromCliStatus, mergeAuthStatus, sameIdentity } from "../auth-status.js";
 import { DEFAULT_CONTEXT_USAGE, makeMockQuery } from "./helpers.js";
 import { randomUUID } from "node:crypto";
+import * as fs from "node:fs/promises";
+import * as path from "node:path";
+import * as os from "node:os";

 const mockQuery = vi.hoisted(() => vi.fn());

@@ -142,6 +145,52 @@ function scriptedTurnQuery(args: any, account: Record<string, unknown>) {
 }

 describe("auth status mappers", () => {
+  it.each([
+    "central proxy start",
+    "/opt/tools/central proxy start --arbitrary-flag",
+    "CeNtRaL ProXy   StArT --return-key",
+    "central.exe proxy\tstart",
+  ])("names the active Central helper %j without exposing its command", (helper) => {
+    const expected = { kind: "gateway", label: "JetBrains Air Gateway" };
+    expect(fromCliStatus(CLI_KEY_HELPER_AND_SUBSCRIPTION, helper)).toEqual(expected);
+    expect(
+      fromAccountInfo(
+        { apiProvider: "firstParty", apiKeySource: "apiKeyHelper", subscriptionType: "max" },
+        helper,
+      ),
+    ).toEqual(expected);
+  });
+
+  it.each([
+    undefined,
+    "",
+    "decentralized proxy start",
+    "centralized proxy start",
+    "central proxy stop",
+    "another proxy start",
+    "central proxy starter",
+  ])("keeps a non-Central helper %j human readable", (helper) => {
+    expect(fromCliStatus(CLI_API_KEY, helper)).toEqual({
+      kind: "api_key",
+      label: "Anthropic API key",
+      detail: "API key helper",
+    });
+  });
+
+  it("does not use an inactive helper or override an external backend", () => {
+    const helper = "central proxy start";
+    expect(fromCliStatus(CLI_BEDROCK, helper)).toEqual({ kind: "external", label: "AWS Bedrock" });
+    expect(fromCliStatus(CLI_LOGGED_OUT, helper)).toEqual({ kind: "none", label: "Not logged in" });
+    expect(fromAccountInfo({ apiProvider: "firstParty", apiKeySource: "env" }, helper)).toEqual({
+      kind: "api_key",
+      label: "Anthropic API key",
+      detail: "env",
+    });
+    expect(fromAccountInfo({ apiKeySource: "futureInternalIdentifier" }, helper)).toEqual({
+      kind: "api_key",
+      label: "Anthropic API key",
+    });
+  });
  it("maps a first-party subscription account", () => {
    expect(
      fromAccountInfo({
@@ -188,7 +237,7 @@ describe("auth status mappers", () => {
    expect(fromCliStatus(CLI_KEY_HELPER_AND_SUBSCRIPTION)).toEqual({
      kind: "api_key",
      label: "Anthropic API key",
-      detail: "apiKeyHelper",
+      detail: "API key helper",
    });
    expect(
      fromAccountInfo({
@@ -201,7 +250,7 @@ describe("auth status mappers", () => {
    ).toEqual({
      kind: "api_key",
      label: "Anthropic API key",
-      detail: "apiKeyHelper",
+      detail: "API key helper",
    });
  });

@@ -244,7 +293,7 @@ describe("auth status mappers", () => {
    expect(fromCliStatus(CLI_API_KEY)).toEqual({
      kind: "api_key",
      label: "Anthropic API key",
-      detail: "apiKeyHelper",
+      detail: "API key helper",
    });
    expect(fromCliStatus(CLI_LOGGED_OUT)).toEqual({
      kind: "none",
@@ -298,7 +347,7 @@ describe("auth status mappers", () => {
    // Key sources identify api_key payloads.
    expect(
      sameIdentity(
-        { kind: "api_key", label: "Anthropic API key", detail: "apiKeyHelper" },
+        { kind: "api_key", label: "Anthropic API key", detail: "API key helper" },
        { kind: "api_key", label: "Anthropic API key", detail: "env" },
      ),
    ).toBe(false);
@@ -317,6 +366,8 @@ describe("auth status over ACP", () => {
   *  Each probe captures the output configured when it was spawned. */
  let deferStatus: boolean;
  let pendingStatus: Array<() => void>;
+  let configDir: string;
+  let originalConfigDir: string | undefined;

  /** Let every already-scheduled promise chain run to completion. */
  function settle() {
@@ -343,7 +394,10 @@ describe("auth status over ACP", () => {
    }
  }

-  beforeEach(() => {
+  beforeEach(async () => {
+    originalConfigDir = process.env.CLAUDE_CONFIG_DIR;
+    configDir = await fs.mkdtemp(path.join(os.tmpdir(), "auth-status-test-"));
+    process.env.CLAUDE_CONFIG_DIR = configDir;
    // Skip native-binary resolution; the exec itself is mocked.
    process.env.CLAUDE_CODE_EXECUTABLE = "claude";
    statusStdout = CLI_SUBSCRIPTION;
@@ -382,7 +436,16 @@ describe("auth status over ACP", () => {
    } as unknown as AcpClient);
  });

-  afterEach(() => {
+  afterEach(async () => {
+    for (const sessionId of Object.keys(agent.sessions)) {
+      await agent.closeSession({ sessionId });
+    }
+    if (originalConfigDir === undefined) {
+      delete process.env.CLAUDE_CONFIG_DIR;
+    } else {
+      process.env.CLAUDE_CONFIG_DIR = originalConfigDir;
+    }
+    await fs.rm(configDir, { recursive: true, force: true });
    delete process.env.CLAUDE_CODE_EXECUTABLE;
    vi.resetAllMocks();
  });
@@ -425,6 +488,94 @@ describe("auth status over ACP", () => {
    return response;
  }

+  it("pushes Central from the effective pre-session settings and suppresses duplicates", async () => {
+    await fs.writeFile(
+      path.join(configDir, "settings.json"),
+      JSON.stringify({
+        apiKeyHelper: "central proxy start --return-key",
+        env: { ANTHROPIC_BASE_URL: "https://example.invalid/private-route" },
+      }),
+    );
+    statusStdout = CLI_API_KEY;
+    await initialize();
+    await vi.waitFor(() =>
+      expect(lastPush()).toEqual({ kind: "gateway", label: "JetBrains Air Gateway" }),
+    );
+    const sessionId = await scriptedSession({
+      apiProvider: "firstParty",
+      apiKeySource: "apiKeyHelper",
+    });
+    await promptOnce(sessionId);
+    expect(updates()).toHaveLength(1);
+    expect(JSON.stringify(updates())).not.toContain("private-route");
+    expect(JSON.stringify(updates())).not.toContain("return-key");
+  });
+
+  it("discards a late probe when programmatic settings replace the active helper", async () => {
+    await fs.writeFile(
+      path.join(configDir, "settings.json"),
+      JSON.stringify({ apiKeyHelper: "ordinary-helper" }),
+    );
+    statusStdout = CLI_API_KEY;
+    deferStatus = true;
+    await initialize();
+    mockQuery.mockImplementation((args: any) =>
+      scriptedTurnQuery(args, { apiKeySource: "apiKeyHelper" }),
+    );
+    const { sessionId } = await agent.newSession({
+      cwd: process.cwd(),
+      mcpServers: [],
+      _meta: {
+        claudeCode: {
+          options: {
+            settings: { apiKeyHelper: "central proxy start" },
+            env: { ANTHROPIC_BASE_URL: "https://example.invalid/override" },
+          },
+        },
+      },
+    });
+    await flushStatus();
+    expect(lastPush()).toEqual({ kind: "gateway", label: "JetBrains Air Gateway" });
+    expect(updates()).toHaveLength(1);
+    expect(statusCalls().at(-1)?.[2]).toMatchObject({
+      cwd: process.cwd(),
+      env: { ANTHROPIC_BASE_URL: "https://example.invalid/override" },
+    });
+    expect(statusCalls().at(-1)?.[1]).toEqual([
+      "auth",
+      "status",
+      "--json",
+      "--settings",
+      JSON.stringify({ apiKeyHelper: "central proxy start" }),
+    ]);
+    await promptOnce(sessionId);
+    await flushStatus();
+    expect(updates()).toHaveLength(1);
+  });
+
+  it("re-probes when a session switches to a Central helper after the initialize probe settled", async () => {
+    await fs.writeFile(
+      path.join(configDir, "settings.json"),
+      JSON.stringify({ apiKeyHelper: "ordinary-helper" }),
+    );
+    statusStdout = CLI_API_KEY;
+    await initialize();
+    expect(lastPush()?.kind).toBe("api_key");
+    const probesBefore = statusCalls().length;
+    mockQuery.mockImplementation((args: any) =>
+      scriptedTurnQuery(args, { apiProvider: "firstParty", apiKeySource: "apiKeyHelper" }),
+    );
+    await agent.newSession({
+      cwd: process.cwd(),
+      mcpServers: [],
+      _meta: { claudeCode: { options: { settings: { apiKeyHelper: "central proxy start" } } } },
+    });
+    await settle();
+    // No prompt yet: the session switch itself must reclassify the helper.
+    expect(statusCalls()).toHaveLength(probesBefore + 1);
+    expect(lastPush()).toEqual({ kind: "gateway", label: "JetBrains Air Gateway" });
+  });
+
  it("pushes the logged-out CLI verdict even though the probe exits non-zero", async () => {
    statusStdout = CLI_LOGGED_OUT;
    statusFails = true;
@@ -580,7 +731,7 @@ describe("auth status over ACP", () => {
        authStatus: {
          kind: "api_key",
          label: "Anthropic API key",
-          detail: "apiKeyHelper",
+          detail: "API key helper",
        },
      },
      {
@@ -615,7 +766,7 @@ describe("auth status over ACP", () => {
    expect(agent.currentAuthStatus).toEqual({
      kind: "api_key",
      label: "Anthropic API key",
-      detail: "apiKeyHelper",
+      detail: "API key helper",
    });
  });

@@ -647,7 +798,7 @@ describe("auth status over ACP", () => {
    expect(agent.currentAuthStatus).toEqual({
      kind: "api_key",
      label: "Anthropic API key",
-      detail: "apiKeyHelper",
+      detail: "API key helper",
    });
  });

--- a/src/tests/authorization.test.ts
+++ b/src/tests/authorization.test.ts
@@ -1,4 +1,7 @@
 import { randomUUID } from "node:crypto";
+import { mkdtemp, rm } from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
 import { describe, expect, it, Mock, vi, afterEach, beforeEach } from "vitest";
 import type { AccountInfo } from "@anthropic-ai/claude-agent-sdk";
 import { AcpClient, ClaudeAcpAgent } from "../acp-agent.js";
@@ -45,7 +48,13 @@ vi.mock("node:child_process", async () => {
 });

 describe("authorization", () => {
-  beforeEach(() => {
+  let configDir: string;
+  let originalConfigDir: string | undefined;
+
+  beforeEach(async () => {
+    originalConfigDir = process.env.CLAUDE_CONFIG_DIR;
+    configDir = await mkdtemp(path.join(os.tmpdir(), "authorization-test-"));
+    process.env.CLAUDE_CONFIG_DIR = configDir;
    vi.useFakeTimers();
    // Skip native-binary resolution; the exec itself is stubbed.
    process.env.CLAUDE_CODE_EXECUTABLE = "claude";
@@ -74,7 +83,7 @@ describe("authorization", () => {
    );
  });

-  afterEach(() => {
+  afterEach(async () => {
    //await all pending events like
    vi.runAllTimers();
    vi.useRealTimers();
@@ -82,6 +91,9 @@ describe("authorization", () => {
    delete process.env.CLAUDE_CODE_EXECUTABLE;
    vi.unstubAllGlobals();
    vi.resetAllMocks();
+    if (originalConfigDir === undefined) delete realProcess.env.CLAUDE_CONFIG_DIR;
+    else realProcess.env.CLAUDE_CONFIG_DIR = originalConfigDir;
+    await rm(configDir, { recursive: true, force: true });
  });

  /** Third element: the `extNotification` spy, so a test can read the
@@ -1124,7 +1136,7 @@ describe("authorization", () => {
        // account by itself — no CLI probe is needed for the post-login state.
        expect(authStatusUpdates(extNotification)).toEqual([
          { kind: "api_key", label: "Anthropic API key", detail: "ANTHROPIC_API_KEY" },
-          { kind: "api_key", label: "Anthropic API key", detail: "apiKeyHelper" },
+          { kind: "api_key", label: "Anthropic API key", detail: "API key helper" },
        ]);
      });

--- a/src/tests/clear-context-coordinator.test.ts
+++ b/src/tests/clear-context-coordinator.test.ts
@@ -1,3 +1,4 @@
+import type { SessionNotification } from "@agentclientprotocol/sdk";
 import { describe, expect, it, vi } from "vitest";
 import {
  ClearContextCoordinatorHost,
@@ -331,6 +332,7 @@ describe("ExitPlanCoordinator", () => {
    const host = {
      ...baseHost,
      sessionUpdate: vi.fn(async () => {}),
+      supportsPlanOperations: () => true,
      destroyReplacement,
      settleCancelledTurn,
      settleFailedTurn: vi.fn(),
@@ -375,6 +377,7 @@ describe("ExitPlanCoordinator", () => {
    const host = {
      ...baseHost,
      sessionUpdate: vi.fn(async () => {}),
+      supportsPlanOperations: () => true,
      destroyReplacement: vi.fn(),
      settleCancelledTurn: vi.fn(),
      settleFailedTurn,
@@ -383,6 +386,8 @@ describe("ExitPlanCoordinator", () => {

    await coordinator.restart("public-session", oldSession, reset);

+    // The plan was never carried out, so it does not become the session's plan.
+    expect(host.sessionUpdate).not.toHaveBeenCalled();
    expect(settleFailedTurn).toHaveBeenCalledWith(oldSession, turn, error);
    expect(turn.carriedUsage).toBeUndefined();
    expect(turn.carriedModelUsage).toBeUndefined();
@@ -390,6 +395,52 @@ describe("ExitPlanCoordinator", () => {
    expect(oldSession.activeTurn).toBeNull();
    expect(oldSession.turnQueue).toEqual([]);
  });
+
+  it.each([
+    ["publishes the approved plan after the session state, before the fresh context runs", true],
+    ["publishes no plan to a client without plan operations", false],
+  ])("%s", async (_, supportsPlanOperations) => {
+    const turn: ClearContextTurn = {
+      settled: false,
+      promptUuid: "00000000-0000-4000-8000-000000000000",
+    };
+    const reset = { toolUseId: "tool-plan", plan: "Ship it", mode: "auto" as const };
+    const oldSession = testSession({ activeTurn: turn, turnQueue: [turn] });
+    const freshSession = testSession();
+    const order: string[] = [];
+    const host = {
+      ...testHost(oldSession, freshSession),
+      sessionUpdate: vi.fn(async ({ update }: SessionNotification) => {
+        order.push(
+          update.sessionUpdate === "plan_update"
+            ? `plan_update ${JSON.stringify(update.plan)}`
+            : update.sessionUpdate,
+        );
+      }),
+      supportsPlanOperations: () => supportsPlanOperations,
+      destroyReplacement: vi.fn(),
+      settleCancelledTurn: vi.fn(),
+      settleFailedTurn: vi.fn(),
+    };
+    vi.mocked(freshSession.input.push).mockImplementation(() => {
+      order.push("continuation");
+    });
+    const coordinator = new ExitPlanCoordinator<TestSession, ClearContextTurn>(host);
+
+    await coordinator.restart("public-session", oldSession, reset);
+
+    expect(order).toEqual([
+      "current_mode_update",
+      "config_option_update",
+      ...(supportsPlanOperations
+        ? [
+            "plan_update " +
+              JSON.stringify({ type: "markdown", planId: "plan-mode", content: "Ship it" }),
+          ]
+        : []),
+      "continuation",
+    ]);
+  });
 });

 describe("observeExitPlanToolResults", () => {
--- a/src/tests/create-session-options.test.ts
+++ b/src/tests/create-session-options.test.ts
@@ -656,9 +656,71 @@ describe("createSession options merging", () => {
      expect(capturedOptions!.settings).toBeUndefined();
    });

-    it("ignores env var when _meta provides settings", async () => {
+    it("keeps model settings when session settings add hooks", async () => {
      process.env.CLAUDE_MODEL_CONFIG = JSON.stringify({
        modelOverrides: { "claude-opus-4-6": "us.anthropic.claude-opus-4-6-v1" },
+        availableModels: ["opus"],
+      });
+      const hooks = { PostToolUse: [{ hooks: [{ type: "command", command: "echo ready" }] }] };
+
+      await agent.newSession({
+        cwd: process.cwd(),
+        mcpServers: [],
+        _meta: { claudeCode: { options: { settings: { hooks } } } },
+      });
+
+      expect(capturedOptions!.settings).toEqual({
+        modelOverrides: { "claude-opus-4-6": "us.anthropic.claude-opus-4-6-v1" },
+        availableModels: ["opus"],
+        hooks,
+      });
+      // The CLI adds these hooks to the ones in the user and project settings.
+      expect(capturedOptions!.settingSources).toEqual(["user", "project", "local"]);
+    });
+
+    it("applies session hooks on session/load with model settings", async () => {
+      process.env.CLAUDE_MODEL_CONFIG = JSON.stringify({ availableModels: ["opus"] });
+      const cwd = process.cwd();
+      const { sessionId } = await agent.newSession({ cwd, mcpServers: [] });
+      const hooks = { Stop: [{ hooks: [{ type: "command", command: "echo done" }] }] };
+
+      await agent.loadSession({
+        sessionId,
+        cwd,
+        mcpServers: [],
+        _meta: { claudeCode: { options: { settings: { hooks } } } },
+      });
+
+      expect(capturedOptions!.resume).toBe(sessionId);
+      expect(capturedOptions!.settings).toEqual({ availableModels: ["opus"], hooks });
+    });
+
+    it("merges model settings with a session settings file", async () => {
+      process.env.CLAUDE_MODEL_CONFIG = JSON.stringify({ availableModels: ["opus"] });
+      const settingsDir = fs.mkdtempSync(path.join(os.tmpdir(), "claude-acp-settings-"));
+      const settingsFile = path.join(settingsDir, "settings.json");
+      fs.writeFileSync(settingsFile, JSON.stringify({ hooks: { Stop: [] } }));
+
+      try {
+        await agent.newSession({
+          cwd: process.cwd(),
+          mcpServers: [],
+          _meta: { claudeCode: { options: { settings: settingsFile } } },
+        });
+
+        expect(capturedOptions!.settings).toEqual({
+          availableModels: ["opus"],
+          hooks: { Stop: [] },
+        });
+      } finally {
+        fs.rmSync(settingsDir, { recursive: true });
+      }
+    });
+
+    it("prefers session settings when both sources set the same field", async () => {
+      process.env.CLAUDE_MODEL_CONFIG = JSON.stringify({
+        modelOverrides: { "claude-opus-4-6": "us.anthropic.claude-opus-4-6-v1" },
+        availableModels: ["opus"],
      });

      await agent.newSession({
@@ -676,10 +738,10 @@ describe("createSession options merging", () => {
        },
      });

-      // _meta settings take precedence; env var is ignored entirely
      expect(capturedOptions!.settings).toEqual({
        model: "claude-sonnet-4-6",
        modelOverrides: { "claude-opus-4-6": "meta-value" },
+        availableModels: ["opus"],
      });
    });

--- a/src/tests/session-doubles.ts
+++ b/src/tests/session-doubles.ts
@@ -64,7 +64,12 @@ export function mockSessionState(
    modes: { currentModeId: "default", availableModes: [] },
    models: { currentModelId: "default", availableModels: [] },
    modelInfos: [],
-    settingsManager: { dispose: vi.fn(), getSettings: () => ({}) },
+    settingsManager: {
+      dispose: vi.fn(),
+      getSettings: () => ({}),
+      getApiKeyHelper: () => undefined,
+      getCwd: () => process.cwd(),
+    },
    accumulatedUsage: {
      inputTokens: 0,
      outputTokens: 0,
--- a/src/tests/session-hooks.test.ts
+++ b/src/tests/session-hooks.test.ts
@@ -0,0 +1,202 @@
+/**
+ * Session hooks against the real Claude Code binary. A local stub of the
+ * Messages API answers every turn, so the test needs no network or account.
+ * The CLI merges the settings tiers, so a mock SDK cannot show that the user
+ * and project hooks still run next to the hooks of `_meta.claudeCode.options`.
+ */
+import { mkdir, mkdtemp, readFile, readdir, rm, writeFile } from "node:fs/promises";
+import http from "node:http";
+import type { AddressInfo } from "node:net";
+import { tmpdir } from "node:os";
+import path from "node:path";
+import type { NewSessionRequest } from "@agentclientprotocol/sdk";
+import { afterAll, afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";
+import { ClaudeAcpAgent, type AcpClient } from "../acp-agent.js";
+
+function sse(type: string, data: object): string {
+  return `event: ${type}\ndata: ${JSON.stringify({ type, ...data })}\n\n`;
+}
+
+const REPLY =
+  sse("message_start", {
+    message: {
+      id: "msg_stub",
+      type: "message",
+      role: "assistant",
+      model: "claude-sonnet-4-5",
+      content: [],
+      stop_reason: null,
+      stop_sequence: null,
+      usage: { input_tokens: 1, output_tokens: 0 },
+    },
+  }) +
+  sse("content_block_start", { index: 0, content_block: { type: "text", text: "" } }) +
+  sse("content_block_delta", { index: 0, delta: { type: "text_delta", text: "ok" } }) +
+  sse("content_block_stop", { index: 0 }) +
+  sse("message_delta", {
+    delta: { stop_reason: "end_turn", stop_sequence: null },
+    usage: { output_tokens: 1 },
+  }) +
+  sse("message_stop", {});
+
+describe("session hooks with the Claude Code binary", () => {
+  let root: string;
+  let cwd: string;
+  let home: string;
+  let log: string;
+  let server: http.Server;
+  let agent: ClaudeAcpAgent;
+  let env: Record<string, string | undefined>;
+  let settingsFiles: Record<string, string>;
+  let logCursor = 0;
+
+  /** A SessionStart hook that writes `tag` to the log. */
+  function hooks(tag: string) {
+    return {
+      SessionStart: [{ hooks: [{ type: "command", command: `echo ${tag} >> "${log}"` }] }],
+    };
+  }
+
+  function meta(tag?: string): NewSessionRequest["_meta"] {
+    return { claudeCode: { options: { env, ...(tag && { settings: { hooks: hooks(tag) } }) } } };
+  }
+
+  /** The hooks that ran since the previous call. Hooks of one event run in parallel. */
+  async function hooksSinceLastCheck(): Promise<string[]> {
+    const lines = (await readFile(log, "utf8").catch(() => "")).split("\n").filter(Boolean);
+    const added = lines.slice(logCursor);
+    logCursor = lines.length;
+    return added.sort();
+  }
+
+  /** A turn finishes after the SessionStart hooks, and it persists the session for a load. */
+  async function finishTurn(sessionId: string): Promise<void> {
+    const response = await agent.prompt({ sessionId, prompt: [{ type: "text", text: "hi" }] });
+    expect(response.stopReason).toBe("end_turn");
+  }
+
+  async function readSettingsFiles(): Promise<Record<string, string>> {
+    const files: Record<string, string> = {};
+    for (const dir of [path.join(home, ".claude"), path.join(cwd, ".claude")]) {
+      for (const name of await readdir(dir)) {
+        if (name.startsWith("settings")) {
+          files[path.join(dir, name)] = await readFile(path.join(dir, name), "utf8");
+        }
+      }
+    }
+    return files;
+  }
+
+  beforeAll(async () => {
+    root = await mkdtemp(path.join(tmpdir(), "claude-acp-session-hooks-"));
+    cwd = path.join(root, "workspace");
+    home = path.join(root, "home");
+    log = path.join(root, "hooks.log");
+    await mkdir(path.join(cwd, ".claude"), { recursive: true });
+    await mkdir(path.join(home, ".claude"), { recursive: true });
+    await writeFile(
+      path.join(home, ".claude", "settings.json"),
+      JSON.stringify({ hooks: hooks("user") }),
+    );
+    await writeFile(
+      path.join(cwd, ".claude", "settings.json"),
+      JSON.stringify({ hooks: hooks("project") }),
+    );
+    settingsFiles = await readSettingsFiles();
+    // vitest.config.ts points every test at `/usr/bin/false` in place of the
+    // CLI. This file opts in to the real binary, and isolates the agent process
+    // too: it reads user settings and runs `claude auth status` itself.
+    vi.stubEnv("CLAUDE_CODE_EXECUTABLE", undefined);
+    vi.stubEnv("HOME", home);
+    vi.stubEnv("CLAUDE_CONFIG_DIR", path.join(home, ".claude"));
+
+    server = http.createServer((req, res) => {
+      req.resume();
+      req.on("end", () => {
+        if (req.url?.startsWith("/v1/messages/count_tokens")) {
+          res.writeHead(200, { "content-type": "application/json" });
+          res.end(JSON.stringify({ input_tokens: 1 }));
+        } else if (req.url?.startsWith("/v1/messages")) {
+          res.writeHead(200, { "content-type": "text/event-stream" });
+          res.end(REPLY);
+        } else {
+          res.writeHead(200);
+          res.end();
+        }
+      });
+    });
+    await new Promise<void>((resolve) => server.listen(0, "127.0.0.1", resolve));
+
+    env = {
+      ...process.env,
+      HOME: home,
+      CLAUDE_CONFIG_DIR: path.join(home, ".claude"),
+      ANTHROPIC_API_KEY: "sk-ant-test",
+      ANTHROPIC_BASE_URL: `http://127.0.0.1:${(server.address() as AddressInfo).port}`,
+      CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC: "1",
+    };
+    const client = {
+      sessionUpdate: async () => {},
+      requestPermission: async () => ({ outcome: { outcome: "cancelled" } }),
+    } as unknown as AcpClient;
+    agent = new ClaudeAcpAgent(client, { log: () => {}, error: () => {} });
+  });
+
+  afterAll(async () => {
+    await agent?.dispose();
+    vi.unstubAllEnvs();
+    await new Promise((resolve) => server?.close(resolve));
+    // The CLI may still write the transcript of the last session after dispose.
+    if (root) await rm(root, { recursive: true, force: true, maxRetries: 10 });
+  });
+
+  // With CLAUDE_MODEL_CONFIG, the adapter passes the merged settings inline.
+  for (const modelConfig of [
+    undefined,
+    '{"modelOverrides":{"claude-opus-4-6":"claude-opus-4-6"}}',
+  ]) {
+    describe(modelConfig ? "with CLAUDE_MODEL_CONFIG" : "without CLAUDE_MODEL_CONFIG", () => {
+      const original = process.env.CLAUDE_MODEL_CONFIG;
+      beforeEach(() => {
+        if (modelConfig) process.env.CLAUDE_MODEL_CONFIG = modelConfig;
+        else delete process.env.CLAUDE_MODEL_CONFIG;
+      });
+      afterEach(() => {
+        if (original === undefined) delete process.env.CLAUDE_MODEL_CONFIG;
+        else process.env.CLAUDE_MODEL_CONFIG = original;
+      });
+
+      it("runs the user, project and IDE hooks of one event, only in their session", async () => {
+        const withHooks = await agent.newSession({ cwd, mcpServers: [], _meta: meta("ide") });
+        await finishTurn(withHooks.sessionId);
+        expect(await hooksSinceLastCheck()).toEqual(["ide", "project", "user"]);
+
+        const withoutHooks = await agent.newSession({ cwd, mcpServers: [], _meta: meta() });
+        await finishTurn(withoutHooks.sessionId);
+        expect(await hooksSinceLastCheck()).toEqual(["project", "user"]);
+
+        expect(await readSettingsFiles()).toEqual(settingsFiles);
+      }, 60_000);
+
+      it("replaces and removes IDE hooks on session/load", async () => {
+        const { sessionId } = await agent.newSession({
+          cwd,
+          mcpServers: [],
+          _meta: meta("ide-old"),
+        });
+        await finishTurn(sessionId);
+        expect(await hooksSinceLastCheck()).toEqual(["ide-old", "project", "user"]);
+
+        await agent.loadSession({ sessionId, cwd, mcpServers: [], _meta: meta("ide-new") });
+        await finishTurn(sessionId);
+        expect(await hooksSinceLastCheck()).toEqual(["ide-new", "project", "user"]);
+
+        await agent.loadSession({ sessionId, cwd, mcpServers: [], _meta: meta() });
+        await finishTurn(sessionId);
+        expect(await hooksSinceLastCheck()).toEqual(["project", "user"]);
+
+        expect(await readSettingsFiles()).toEqual(settingsFiles);
+      }, 60_000);
+    });
+  }
+});
--- a/src/tests/settings-api-key-helper.test.ts
+++ b/src/tests/settings-api-key-helper.test.ts
@@ -0,0 +1,40 @@
+import { describe, expect, it, vi } from "vitest";
+
+const resolved = vi.hoisted(() => ({ value: undefined as unknown }));
+
+vi.mock("@anthropic-ai/claude-agent-sdk", async (importOriginal) => ({
+  ...(await importOriginal<typeof import("@anthropic-ai/claude-agent-sdk")>()),
+  resolveSettings: async () => resolved.value,
+}));
+
+const { SettingsManager } = await import("../settings.js");
+
+async function managerResolving(value: unknown) {
+  resolved.value = value;
+  const manager = new SettingsManager(process.cwd());
+  await manager.initialize();
+  return manager;
+}
+
+describe("SettingsManager.getApiKeyHelper", () => {
+  it("prefers a managed helper over the --settings override", async () => {
+    const manager = await managerResolving({
+      effective: { apiKeyHelper: "managed-helper" },
+      provenance: { apiKeyHelper: { source: "managed" } },
+      sources: [],
+    });
+    expect(manager.getApiKeyHelper({ apiKeyHelper: "override-helper" })).toBe("managed-helper");
+    manager.dispose();
+  });
+
+  it("prefers the --settings override over a user helper", async () => {
+    const manager = await managerResolving({
+      effective: { apiKeyHelper: "user-helper" },
+      provenance: { apiKeyHelper: { source: "userSettings" } },
+      sources: [],
+    });
+    expect(manager.getApiKeyHelper({ apiKeyHelper: "override-helper" })).toBe("override-helper");
+    expect(manager.getApiKeyHelper()).toBe("user-helper");
+    manager.dispose();
+  });
+});
--- a/src/tests/tool-call-contract.test.ts
+++ b/src/tests/tool-call-contract.test.ts
@@ -5,7 +5,7 @@ import * as path from "node:path";
 import type { ClientCapabilities } from "@agentclientprotocol/sdk";
 import { AcpClient, toAcpNotifications, ToolUseCache } from "../acp-agent.js";
 import { ClientCapabilities as ToolCallCapabilities } from "../tool-calls/client-capabilities.js";
-import { backgroundedBashToolCall } from "../tool-calls/background.js";
+import { backgroundedBashToolCall, withRunningTerminal } from "../tool-calls/background.js";
 import { ChangedMetaFilter } from "../tool-calls/changed-meta-filter.js";
 import { ToolCallFieldTracker } from "../tool-calls/field-tracker.js";
 import { AcpToolCallRenderer } from "../tool-calls/renderer.js";
@@ -738,4 +738,29 @@ describe("background Bash", () => {
  it("sends no marker to a client without the asyncTasks capability", () => {
    expect(backgroundedBashToolCall(completed, new Set(["t"]), false)).toBe(completed);
  });
+
+  const exit = { terminal_id: "t", exit_code: null, signal: null };
+
+  it("keeps the terminal of a command in the background running", () => {
+    const withExit = {
+      ...completed,
+      update: {
+        ...completed.update,
+        _meta: { claudeCode: { toolName: "Bash" }, terminal_exit: exit },
+      },
+    };
+    expect(withRunningTerminal(withExit, "t")).toEqual({
+      ...completed,
+      update: { ...completed.update, _meta: { claudeCode: { toolName: "Bash" } } },
+    });
+    expect(withRunningTerminal(withExit, "other")).toBe(withExit);
+  });
+
+  it("leaves out a `_meta` that held only the terminal's exit, which v2 would store as empty", () => {
+    const onlyExit = {
+      ...completed,
+      update: { ...completed.update, _meta: { terminal_exit: exit } },
+    };
+    expect(withRunningTerminal(onlyExit, "t")).toEqual(completed);
+  });
 });
--- a/src/tests/tools.test.ts
+++ b/src/tests/tools.test.ts
@@ -3820,6 +3820,31 @@ describe("tool_result_meta non-execution stamping", () => {
    });
  });

+  it("reports an interrupted command as cancelled to a v2 client, and as completed to every other client", () => {
+    const status = (interrupted: boolean, toolCallCapabilities?: ToolCallCapabilities) =>
+      toAcpNotifications(
+        [{ type: "tool_result", tool_use_id: "toolu_bash", content: "partial" }] as any,
+        "user",
+        "test-session",
+        { toolu_bash: bashToolUse },
+        mockClient,
+        mockLogger,
+        {
+          toolUseResult: { stdout: "partial", stderr: "", interrupted, isImage: false },
+          ...(toolCallCapabilities ? { toolCallCapabilities } : {}),
+        },
+      ).at(-1)?.update;
+    const v2 = ToolCallCapabilities.from({}, { v2: true });
+
+    expect(status(true, v2)).toMatchObject({ status: "cancelled" });
+    expect(status(false, v2)).toMatchObject({ status: "completed" });
+    // v1 has no cancelled status.
+    expect(status(true)).toMatchObject({ status: "completed" });
+    expect(status(true, ToolCallCapabilities.from(AIR_CLIENT))).toMatchObject({
+      status: "completed",
+    });
+  });
+
  it("closes a tool call that Claude dropped before it ran as cancelled on v2, and as failed elsewhere", () => {
    const unfinished = (ran: boolean, capabilities?: ToolCallCapabilities) =>
      new AcpToolCallRenderer(capabilities).unfinished({ toolCallId: "toolu_bash", ran });
@@ -4641,3 +4666,102 @@ describe("NotebookEdit", () => {
    expect(notifications[0].update).not.toHaveProperty("rawOutput");
  });
 });
+
+// A plan that the user approves through ExitPlanMode becomes the session's
+// markdown plan for a client that supports plan operations.
+describe("toAcpNotifications - the plan of an approved ExitPlanMode", () => {
+  const mockClient = {} as AcpClient;
+  const mockLogger: Logger = { log: () => {}, error: () => {} };
+
+  /** The plan updates for the result of an ExitPlanMode call with `input`. */
+  function planUpdates(
+    result: Record<string, unknown> = {},
+    options: Parameters<typeof toAcpNotifications>[6] = {},
+    input: Record<string, unknown> = { plan: "Implement it", planFilePath: "/plans/p.md" },
+  ) {
+    return toAcpNotifications(
+      [
+        {
+          type: "tool_result",
+          tool_use_id: "toolu_plan",
+          content: "User has approved your plan. You can now start coding.",
+          ...result,
+        },
+      ] as any,
+      "user",
+      "test-session",
+      { toolu_plan: { type: "tool_use", id: "toolu_plan", name: "ExitPlanMode", input } },
+      mockClient,
+      mockLogger,
+      { clientCapabilities: { plan: {} }, ...options },
+    )
+      .filter(({ update }) => update.sessionUpdate === "plan_update")
+      .map(({ update }) => update);
+  }
+
+  const markdownPlan = (content: string) => ({
+    sessionUpdate: "plan_update",
+    plan: { type: "markdown", planId: "plan-mode", content },
+  });
+
+  it("shows the plan of the structured result, which includes the user's edits", () => {
+    const toolUseResult = { plan: "Implement it carefully", isAgent: false, planWasEdited: true };
+    expect(planUpdates({}, { toolUseResult })).toEqual([markdownPlan("Implement it carefully")]);
+  });
+
+  it("shows the plan of the input, trimmed, when there is no structured result, as on replay", () => {
+    expect(planUpdates({}, {}, { plan: "\nImplement it\n" })).toEqual([
+      markdownPlan("Implement it"),
+    ]);
+  });
+
+  it("shows the plan of the input when the structured result has none", () => {
+    const toolUseResult = { plan: null, isAgent: false };
+    expect(planUpdates({}, { toolUseResult })).toEqual([markdownPlan("Implement it")]);
+  });
+
+  it("shows the plan after the tool call's result", () => {
+    const toolUseResult = { plan: "Implement it", isAgent: false };
+    const kinds = toAcpNotifications(
+      [{ type: "tool_result", tool_use_id: "toolu_plan", content: "Approved." }] as any,
+      "user",
+      "test-session",
+      {
+        toolu_plan: {
+          type: "tool_use",
+          id: "toolu_plan",
+          name: "ExitPlanMode",
+          input: { plan: "Implement it" },
+        },
+      },
+      mockClient,
+      mockLogger,
+      { clientCapabilities: { plan: {} }, toolUseResult },
+    ).map(({ update }) => update.sessionUpdate);
+    expect(kinds).toEqual(["tool_call_update", "plan_update"]);
+  });
+
+  it("shows nothing to a client without plan operations", () => {
+    expect(planUpdates({}, { clientCapabilities: {} })).toEqual([]);
+  });
+
+  it("shows nothing for a plan the user rejected", () => {
+    expect(planUpdates({ is_error: true, content: "The user chose to keep planning." })).toEqual(
+      [],
+    );
+  });
+
+  it("shows nothing for a subagent's plan", () => {
+    expect(planUpdates({}, { parentToolUseId: "toolu_agent" })).toEqual([]);
+    expect(planUpdates({}, { toolUseResult: { plan: "Implement it", isAgent: true } })).toEqual([]);
+  });
+
+  it("shows nothing for a plan that waits for its team lead", () => {
+    const toolUseResult = { plan: "Implement it", isAgent: false, awaitingLeaderApproval: true };
+    expect(planUpdates({}, { toolUseResult })).toEqual([]);
+  });
+
+  it("shows nothing for an empty plan", () => {
+    expect(planUpdates({}, {}, { plan: "  " })).toEqual([]);
+  });
+});
--- a/src/tests/turn-events.test.ts
+++ b/src/tests/turn-events.test.ts
@@ -6,7 +6,7 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import type { RequestPermissionRequest, SessionNotification } from "@agentclientprotocol/sdk";
 import type { AcpClient, ClaudeAcpAgent } from "../acp-agent.js";
-import type { TurnEvents } from "../turn-events.js";
+import type { ForegroundEvents, TurnEvents } from "../turn-events.js";
 import { DEFAULT_CONTEXT_USAGE } from "./helpers.js";
 import { randomUUID } from "node:crypto";

@@ -137,8 +137,6 @@ function recordEvents(log: string[] = [], label?: string) {
  const push = (entry: string) => log.push(label ? `${label} ${entry}` : entry);
  const events: TurnEvents = {
    inserted: (messageId) => push(`inserted ${messageId}`),
-    awaitingUser: () => push("awaitingUser"),
-    resumed: () => push("resumed"),
    ended: (outcome) => {
      push(`ended ${outcome.stopReason}`);
      done.resolve();
@@ -199,24 +197,37 @@ describe("turn events", () => {
  let backgroundAnswer: PromiseWithResolvers<void>;
  /** Sees each session update; the agent waits until it returns. */
  let onSessionUpdate: (notification: SessionNotification) => Promise<void> | void;
+  /** What the agent reported of the session's foreground work. */
+  let foreground: string[];

  beforeEach(async () => {
    vi.resetModules();
    permissionRequests = [];
    backgroundAnswer = Promise.withResolvers<void>();
    onSessionUpdate = () => {};
+    foreground = [];
    const { ClaudeAcpAgent } = await import("../acp-agent.js");
-    agent = new ClaudeAcpAgent({
-      sessionUpdate: async (notification: SessionNotification) => onSessionUpdate(notification),
-      extNotification: async () => {},
-      requestPermission: async (request: RequestPermissionRequest) => {
-        permissionRequests.push(request);
-        await new Promise((resolve) => setTimeout(resolve, 1));
-        if (request.toolCall.toolCallId === "toolu_background") await backgroundAnswer.promise;
-        const allow = request.options.find((option) => option.kind === "allow_once");
-        return { outcome: { outcome: "selected", optionId: allow!.optionId } };
-      },
-    } as unknown as AcpClient);
+    const foregroundEvents: ForegroundEvents = {
+      running: () => foreground.push("running"),
+      awaitingUser: () => foreground.push("awaitingUser"),
+      ended: (outcome) => foreground.push(`ended ${outcome.stopReason}`),
+      failed: () => foreground.push("failed"),
+    };
+    agent = new ClaudeAcpAgent(
+      {
+        sessionUpdate: async (notification: SessionNotification) => onSessionUpdate(notification),
+        extNotification: async () => {},
+        requestPermission: async (request: RequestPermissionRequest) => {
+          permissionRequests.push(request);
+          await new Promise((resolve) => setTimeout(resolve, 1));
+          if (request.toolCall.toolCallId === "toolu_background") await backgroundAnswer.promise;
+          const allow = request.options.find((option) => option.kind === "allow_once");
+          return { outcome: { outcome: "selected", optionId: allow!.optionId } };
+        },
+      } as unknown as AcpClient,
+      undefined,
+      { foreground: () => foregroundEvents },
+    );
  });

  afterEach(async () => {
@@ -347,7 +358,78 @@ describe("turn events", () => {
    await turn.done;

    expect(permissionRequests).toHaveLength(1);
-    expect(turn.log.slice(1)).toEqual(["awaitingUser", "resumed", "ended end_turn"]);
+    expect(turn.log.slice(1)).toEqual(["ended end_turn"]);
+    expect(foreground).toEqual(["running", "awaitingUser", "running", "ended end_turn"]);
+  });
+
+  it("reports waiting on a request that Claude Code opens for a started turn before its echo", async () => {
+    let whileOpen: string[] = [];
+    scriptQuery(async function* (input, options) {
+      const { value } = await input.next();
+      yield lifecycle(value.uuid, "started", options.sessionId!);
+      // Claude Code asks for the prompt before the consumer reaches its echo.
+      // The user answers it only once the test resolves `backgroundAnswer`.
+      const decision = options.canUseTool!(
+        "Bash",
+        { command: "ls" },
+        { signal: new AbortController().signal, suggestions: [], toolUseID: "toolu_background" },
+      );
+      await vi.waitFor(() => expect(permissionRequests).toHaveLength(1));
+      whileOpen = [...foreground];
+      backgroundAnswer.resolve();
+      await decision;
+      yield echo(value, options.sessionId!);
+      yield {
+        type: "user",
+        message: {
+          role: "user",
+          content: [{ type: "tool_result", tool_use_id: "toolu_background", content: "README.md" }],
+        },
+        parent_tool_use_id: null,
+        uuid: randomUUID(),
+        session_id: options.sessionId!,
+      };
+      yield result(options.sessionId!);
+      await input.next();
+    });
+    const sessionId = await newSession();
+    const turn = recordEvents();
+
+    await agent.startTurn(prompt(sessionId, "list files"), turn.events);
+    await turn.done;
+
+    expect(whileOpen).toEqual(["running", "awaitingUser"]);
+    expect(foreground).toEqual(["running", "awaitingUser", "running", "ended end_turn"]);
+  });
+
+  it("reports work that starts while a request is open as waiting at once", async () => {
+    let atStart: string[] = [];
+    scriptQuery(async function* (input, options) {
+      const { value } = await input.next();
+      // A request that no work opened, such as a background task's. The user
+      // answers it only once the test resolves `backgroundAnswer`.
+      const background = options.canUseTool!(
+        "Bash",
+        { command: "sleep 60" },
+        { signal: new AbortController().signal, suggestions: [], toolUseID: "toolu_background" },
+      );
+      await vi.waitFor(() => expect(permissionRequests).toHaveLength(1));
+      yield lifecycle(value.uuid, "started", options.sessionId!);
+      // Before the prompt's echo, which would report the request too.
+      atStart = [...foreground];
+      backgroundAnswer.resolve();
+      await background;
+      yield echo(value, options.sessionId!);
+      yield result(options.sessionId!);
+      await input.next();
+    });
+    const sessionId = await newSession();
+    const turn = recordEvents();
+
+    await agent.startTurn(prompt(sessionId, "list files"), turn.events);
+    await turn.done;
+
+    expect(atStart).toEqual(["running", "awaitingUser"]);
  });

  it("awaits the user while any request in the session is open, also one opened before the turn", async () => {
@@ -368,13 +450,13 @@ describe("turn events", () => {
        );
      },
      async function* (options) {
-        atStart = [...second.log];
+        atStart = [...foreground];
        await options.canUseTool(
          "Bash",
          { command: "ls" },
          { signal: new AbortController().signal, suggestions: [], toolUseID: "toolu_ls" },
        );
-        afterOwnAnswer = [...second.log];
+        afterOwnAnswer = [...foreground];
        await backgroundRequest;
        yield {
          type: "user",
@@ -399,11 +481,19 @@ describe("turn events", () => {
    await second.done;

    expect(first.log.slice(1)).toEqual(["ended end_turn"]);
-    // Waiting from insertion, through its own answered request, until the
-    // earlier request is answered too.
-    expect(atStart.slice(1)).toEqual(["awaitingUser"]);
-    expect(afterOwnAnswer!.slice(1)).toEqual(["awaitingUser"]);
-    expect(second.log.slice(1)).toEqual(["awaitingUser", "resumed", "ended end_turn"]);
+    // The first turn's work ended before the background request opened, and
+    // the second turn waits from insertion, through its own answered request,
+    // until the earlier request is answered too.
+    const firstWork = ["running", "ended end_turn"];
+    expect(atStart).toEqual([...firstWork, "running", "awaitingUser"]);
+    expect(afterOwnAnswer).toEqual([...firstWork, "running", "awaitingUser"]);
+    expect(foreground).toEqual([
+      ...firstWork,
+      "running",
+      "awaitingUser",
+      "running",
+      "ended end_turn",
+    ]);
  });

  it("ends a queued turn that is cancelled before it is inserted, without inserting it", async () => {
--- a/src/tool-calls/background.ts
+++ b/src/tool-calls/background.ts
@@ -42,3 +42,33 @@ export function backgroundedBashToolCall(
    },
  };
 }
+
+/**
+ * Keeps the display terminal of a command that went to the background running:
+ * drops `terminal_exit` from the tool result update of `toolCallId`.
+ *
+ * The Bash call returns as soon as the command detaches, so that exit would
+ * mark the terminal as ended while the command still runs. The consumer sends
+ * the exit when the command's task ends (see `Session.backgroundTerminals`).
+ */
+export function withRunningTerminal(
+  notification: SessionNotification,
+  toolCallId: string | undefined,
+): SessionNotification {
+  const update = notification.update;
+  if (
+    toolCallId === undefined ||
+    update.sessionUpdate !== "tool_call_update" ||
+    update.toolCallId !== toolCallId ||
+    !update._meta ||
+    !("terminal_exit" in update._meta)
+  ) {
+    return notification;
+  }
+  const meta = { ...update._meta };
+  delete meta.terminal_exit;
+  const next: typeof update = { ...update, _meta: meta };
+  // An empty `_meta` would clear what a v2 client stores for the tool call.
+  if (Object.keys(meta).length === 0) delete next._meta;
+  return { ...notification, update: next };
+}
--- a/src/tool-calls/renderer.ts
+++ b/src/tool-calls/renderer.ts
@@ -44,11 +44,13 @@ export type ToolUpdateMeta = {
  claudeCode?: {
    /* The name of the tool that was used in Claude Code. Also carried as the
       standard ACP `name` field on the initial `tool_call`. A progress beat
-       for AIR leaves it out when the adapter does not know the tool. */
+       for AIR leaves it out when the adapter does not know the tool. A v2
+       client gets it as `name` alone (see `V2ToolCallMeta`). */
    toolName?: string;
-    /* The structured output provided by Claude Code. For an AIR client, a
-       PostToolUse update carries only the `status` and `isAsync` markers of
-       the tool_response: the tool output itself is in the tool-call content. */
+    /* The structured output provided by Claude Code. For an AIR or a v2
+       client, a PostToolUse update carries only the `status` and `isAsync`
+       markers of the tool_response: the tool output itself is in the
+       tool-call content. */
    toolResponse?: unknown;
    /* For a tool call made inside a subagent: the tool_use id of the
       Agent/Task call that spawned the subagent. Mirrors the SDK's
@@ -151,14 +153,31 @@ export class AcpToolCallRenderer {
  }

  /**
-   * The status of a tool result. `nonExecution` is why Claude Code stamped an
-   * error result instead of the tool's output. A run that was aborted is
-   * `cancelled` for a v2 client, which has that status; every other client
-   * gets `failed`, with the kind in `_meta.claudeCode.nonExecutionKind`.
+   * Whether the client keeps a tool call's `_meta` across reports: AIR merges
+   * its keys, and v2 stores it. Such a client gets no `toolResponse` text that
+   * the tool call's content already shows, which it would otherwise keep.
   */
-  resultStatus(isError: boolean, nonExecution: ToolResultMeta | undefined): ToolCallStatus {
-    if (!isError) return "completed";
-    return this.capabilities.v2 && isAbortedToolResult(nonExecution) ? V2_CANCELLED : "failed";
+  private get keepsMeta(): boolean {
+    return this.capabilities.air.client || this.capabilities.v2;
+  }
+
+  /**
+   * The status of a tool result. Claude Code reports a run that it aborted in
+   * one of two ways: an error result whose `nonExecution` kind says so (a
+   * cancelled turn), or a command result that says `interrupted` (for example,
+   * a steering message landed just before the command started). Such a run is
+   * `cancelled` for a v2 client, which has that status. Every other client gets
+   * `failed` for the error, with the kind in `_meta.claudeCode.nonExecutionKind`,
+   * and `completed` for the command.
+   */
+  resultStatus(
+    isError: boolean,
+    nonExecution: ToolResultMeta | undefined,
+    interrupted = false,
+  ): ToolCallStatus {
+    const aborted = interrupted || (isError && isAbortedToolResult(nonExecution));
+    if (this.capabilities.v2 && aborted) return V2_CANCELLED;
+    return isError ? "failed" : "completed";
  }

  /** The facts of a tool use. */
@@ -332,7 +351,14 @@ export class AcpToolCallRenderer {

  /** The result fields of a tool result, before the status and the tool name. */
  resultFields(toolUse: ToolUse, result: ResultBlock, structured?: unknown): RenderedResult {
-    const facts = this.resultFacts(toolUse, result, structured);
+    return this.fieldsOfResult(toolUse, result, this.resultFacts(toolUse, result, structured));
+  }
+
+  private fieldsOfResult(
+    toolUse: ToolUse,
+    result: ResultBlock,
+    facts: ToolResultFacts,
+  ): RenderedResult {
    const { command, ...fields } = facts;
    if (!command) return fields;
    // The terminal was announced under the tool_use id (see `toolCall`), so the
@@ -397,7 +423,8 @@ export class AcpToolCallRenderer {
    result: ResultBlock,
    options: { structured?: unknown; nonExecution?: ToolResultMeta } = {},
  ): ToolCallUpdate[] {
-    const { _meta: resultMeta, ...fields } = this.resultFields(toolUse, result, options.structured);
+    const facts = this.resultFacts(toolUse, result, options.structured);
+    const { _meta: resultMeta, ...fields } = this.fieldsOfResult(toolUse, result, facts);
    // AIR shows a read or a search that names a path as the list of viewed
    // files. That view does not show the text of the result, so it stays out.
    const viewedFiles =
@@ -445,7 +472,11 @@ export class AcpToolCallRenderer {
      } satisfies ToolUpdateMeta,
      toolCallId: toolUse.id,
      sessionUpdate: "tool_call_update",
-      status: this.resultStatus(result.is_error === true, options.nonExecution),
+      status: this.resultStatus(
+        result.is_error === true,
+        options.nonExecution,
+        facts.command?.interrupted === true,
+      ),
      ...(rawOutput !== undefined ? { rawOutput } : {}),
      ...(planFilePath ? { rawInput: planFileInput(toolUse.input, planFilePath) } : {}),
      ...fields,
@@ -486,7 +517,8 @@ export class AcpToolCallRenderer {
  /**
   * The report of a PostToolUse hook: the final change of an edit tool, and
   * the `status` and `isAsync` markers of the `tool_response`. The rest of the
-   * `tool_response` repeats output that the content already carries.
+   * `tool_response` repeats output that the content already carries, such as
+   * the whole text of a written file.
   */
  async hookResult(
    toolUse: Pick<ToolUse, "id" | "name">,
@@ -497,7 +529,7 @@ export class AcpToolCallRenderer {
    const change = reporter.hookResult
      ? await reporter.hookResult(toolResponse, { cwd, capabilities: this.capabilities })
      : {};
-    if (!this.capabilities.air.client) {
+    if (!this.keepsMeta) {
      // The upstream shape: the whole tool_response, on every hook.
      return {
        _meta: { claudeCode: { toolResponse, toolName: toolUse.name } } satisfies ToolUpdateMeta,
@@ -567,9 +599,10 @@ export class AcpToolCallRenderer {
    message?: string;
  }): ToolCallUpdate {
    const reason = denial.decisionReason ?? denial.message;
-    // AIR gets the SDK message only when it differs from the reason, which
-    // the content shows. Every other client gets the upstream toolResponse.
-    const extraMessage = !this.capabilities.air.client
+    // AIR and v2 get the SDK message only when it differs from the reason,
+    // which the content shows. Every other client gets the upstream
+    // toolResponse.
+    const extraMessage = !this.keepsMeta
      ? { decisionReason: denial.decisionReason, message: denial.message }
      : denial.decisionReason !== undefined &&
          denial.message !== undefined &&
--- a/src/turn-events.ts
+++ b/src/turn-events.ts
@@ -1,10 +1,11 @@
 /**
- * A prompt turn as the adapter understands it, independent of the ACP version.
+ * A prompt turn and the foreground work of a session, as the adapter
+ * understands them, independent of the ACP version.
 *
- * The agent reports each turn through {@link TurnEvents}, and each ACP version
- * maps the events to its own messages. ACP v1 answers `session/prompt` when the
- * turn ends or fails. ACP v2 answers it when the prompt is inserted, and
- * reports the rest as session state.
+ * The agent reports how each prompt is answered through {@link TurnEvents}:
+ * ACP v1 answers `session/prompt` when the turn ends or fails, and ACP v2 when
+ * the prompt is inserted. ACP v2 also reports the session's work as state,
+ * which the agent reports through {@link ForegroundEvents}.
 *
 * The agent calls these synchronously while it updates its own state, so a
 * handler must not throw, nor call back into the agent before it returns.
@@ -23,18 +24,6 @@ export interface TurnEvents {
   * `/compact`), it is the command's result, after any output it streamed.
   */
  inserted(messageId: string): void;
-  /**
-   * The turn waits for the user: a permission request or a question is open in
-   * the session. Requests do not say which prompt they are for, so this
-   * includes one opened before the turn was inserted. Only reported after
-   * {@link inserted}.
-   */
-  awaitingUser(): void;
-  /**
-   * The turn works again: no request is open any more. A turn that ends or
-   * fails while it waits reports that instead.
-   */
-  resumed(): void;
  /**
   * The turn ended. A queued turn that is cancelled before it is inserted
   * ends too, without {@link inserted}; Claude Code may still run its prompt.
@@ -48,6 +37,40 @@ export interface TurnEvents {
  failed(error: unknown): void;
 }

+/**
+ * The foreground work of a session: what a client would wait for before it
+ * sends the next prompt. One piece of work runs at a time, and the next starts
+ * with {@link running}. The work is either:
+ *
+ * - A prompt's turn, from {@link TurnEvents.inserted} until its result, or
+ *   until it fails or is cancelled. A turn that v1 holds open for the
+ *   background subagents it spawned (`Turn.deferredSettle`) ends its work at
+ *   its result all the same: the hold only delays v1's answer.
+ * - A model cycle that Claude Code starts on its own while no work runs: for
+ *   example, its follow-up after a background command or subagent finished,
+ *   or its answer to a message from another session. It runs until its result.
+ *
+ * A prompt that Claude Code takes in while a cycle runs takes the cycle over:
+ * the cycle reports nothing more, and the turn reports from there.
+ */
+export interface ForegroundEvents {
+  /** The work started, or works again after it waited for the user. */
+  running(): void;
+  /**
+   * The work waits for the user: a permission request or a question is open in
+   * the session. Requests do not say which work they are for, so this includes
+   * one opened before the work started.
+   */
+  awaitingUser(): void;
+  /** The work ended. */
+  ended(outcome: TurnOutcome): void;
+  /**
+   * The work failed with `error`, the JSON-RPC error that v1 answers the
+   * prompt with.
+   */
+  failed(error: unknown): void;
+}
+
 /** Why a turn ended. Every ACP version has these reasons. */
 export type StopReason = "end_turn" | "max_tokens" | "max_turn_requests" | "refusal" | "cancelled";

--- a/src/v2/agent.ts
+++ b/src/v2/agent.ts
@@ -19,9 +19,9 @@ import type { AcpSessionNotification } from "../acp-subagents.js";
 import type { AcpPermissionRequest } from "../permissions/presentation.js";
 import { v1InitializeRequest, v2InitializeResponse } from "./initialize.js";
 import { v1PermissionResponse, v2PermissionRequest } from "./permission.js";
-import { v2Prompt } from "./prompt.js";
+import { v2Foreground, v2Prompt } from "./prompt.js";
 import {
-  v1ForkSessionRequests,
+  v1ForkSessionRequest,
  v1NewSessionRequest,
  v1RestoreSessionRequest,
  v1SetSessionConfigOptionRequest,
@@ -32,6 +32,7 @@ import {
 } from "./session.js";
 import { v2SessionUpdate } from "./session-update.js";
 import { V2Terminals } from "./terminal.js";
+import { V2ToolCallMeta } from "./tool-call-meta.js";

 /**
 * The ACP v2 surface, for one connection.
@@ -52,7 +53,13 @@ export function v2AgentApp(
    .agent({ name: "claude-code-acp" })
    .onConnect((connection) => {
      client = new V2ClientConnection(connection.client, logger ?? console);
-      agent = new ClaudeAcpAgent(client, logger, { v2: true });
+      agent = new ClaudeAcpAgent(client, logger, {
+        v2: true,
+        foreground: (sessionId) =>
+          v2Foreground((update) => {
+            void client.send({ sessionId, update });
+          }),
+      });
      onAgent(agent);
    })
    .onRequest(v2.methods.agent.initialize, async ({ params }) =>
@@ -87,17 +94,18 @@ export function v2AgentApp(
      };
    })
    .onRequest(v2.methods.agent.session.fork, async ({ params }) => {
-      const requests = v1ForkSessionRequests(params);
-      const { sessionId } = await agent.unstable_forkSession(requests.fork);
+      // The agent starts the forked session, so the client can prompt it.
+      const response = await agent.unstable_forkSession(v1ForkSessionRequest(params));
      return {
-        sessionId,
-        ...v2ResumeSessionResponse(await agent.resumeSession(requests.resume(sessionId))),
-        ...(await setupCommands(agent, sessionId, logger)),
+        sessionId: response.sessionId,
+        ...v2ResumeSessionResponse(response),
+        ...(await setupCommands(agent, response.sessionId, logger)),
      };
    })
    .onRequest(v2.methods.agent.session.close, async ({ params }) => {
      const response = await agent.closeSession(params);
      client.terminals.forget(params.sessionId);
+      client.toolCallMeta.forget(params.sessionId);
      return response;
    })
    .onRequest(v2.methods.agent.session.delete, ({ params }) => agent.deleteSession(params))
@@ -151,6 +159,9 @@ class V2ClientConnection implements AcpClient {
  /** The display terminals of the commands that the agent runs. */
  readonly terminals = new V2Terminals();

+  /** The `_meta` that the client stores for each tool call. */
+  readonly toolCallMeta = new V2ToolCallMeta();
+
  constructor(
    private readonly ctx: v2.AgentContext,
    private readonly logger: Logger,
@@ -211,7 +222,8 @@ class V2ClientConnection implements AcpClient {

  /**
   * The v2 updates of a v1 update: for a tool call report, the updates of its
-   * terminal first, then the report itself (see {@link V2Terminals}).
+   * terminal first (see {@link V2Terminals}), then the report itself, with the
+   * `_meta` that the client stores (see {@link V2ToolCallMeta}).
   */
  private v2Updates(
    sessionId: string,
@@ -222,7 +234,9 @@ class V2ClientConnection implements AcpClient {
      return v2Update ? [v2Update] : [];
    }
    const { terminal, report } = this.terminals.split(sessionId, update);
-    const reportUpdate = report && v2SessionUpdate(report);
+    if (!report) return terminal;
+    const starts = report.sessionUpdate === "tool_call";
+    const reportUpdate = v2SessionUpdate(this.toolCallMeta.apply(sessionId, report, starts));
    return [...terminal, ...(reportUpdate ? [reportUpdate] : [])];
  }

@@ -246,9 +260,11 @@ class V2ClientConnection implements AcpClient {
    params: AcpPermissionRequest,
    signal?: AbortSignal,
  ): Promise<RequestPermissionResponse> {
+    // The subject is an update of the tool call, with its stored `_meta`.
+    const toolCall = this.toolCallMeta.subject(params.sessionId, params.toolCall);
    const response = await this.ctx.request(
      v2.methods.client.session.requestPermission,
-      v2PermissionRequest(params),
+      v2PermissionRequest({ ...params, toolCall }),
      { cancellationSignal: signal },
    );
    return v1PermissionResponse(response);
--- a/src/v2/initialize.ts
+++ b/src/v2/initialize.ts
@@ -32,6 +32,10 @@ export function v1InitializeRequest(request: v2.InitializeRequest): InitializeRe
      // compaction as a compaction entity rather than as a "Compact
      // conversation" tool call, also on replay.
      session: { configOptions: { boolean: {} }, notices: {}, compaction: {} },
+      // Every v2 client takes `plan_update`, with the draft's markdown and file
+      // plans, and `plan_removed`; v1 asks for the `plan` marker. With it, the
+      // agent shows an approved ExitPlanMode plan as a markdown plan.
+      plan: {},
      // v1 marks terminal auth support with a boolean, v2 with an object.
      auth: {
        terminal: capabilities?.auth?.terminal != null,
@@ -89,7 +93,7 @@ export function v2InitializeResponse(response: InitializeResponse): v2.Initializ
 * - The session baseline: `session/new`, `list`, `resume` (with replay),
 *   `close`, `prompt`, `cancel`, and `update`.
 * - `session/delete`, `session/fork` (which returns a session the client can
- *   prompt, see `v1ForkSessionRequests`), and `additionalDirectories`.
+ *   prompt at once), and `additionalDirectories`.
 * - The prompt content and MCP transports that the agent's v1 `initialize`
 *   lists: images, embedded context, and HTTP servers. Stdio servers are in the
 *   v1 baseline; v2 has no SSE transport.
--- a/src/v2/prompt.ts
+++ b/src/v2/prompt.ts
@@ -13,31 +13,19 @@ import {
 } from "@agentclientprotocol/sdk";
 import * as v2 from "@agentclientprotocol/sdk/experimental/v2";
 import type { ClaudeAcpAgent } from "../acp-agent.js";
-import type { StopReason, TurnEvents, TurnOutcome } from "../turn-events.js";
+import type { ForegroundEvents, StopReason, TurnEvents, TurnOutcome } from "../turn-events.js";

 /**
 * Starts a turn for `params`, and answers when Claude Code takes the prompt
- * in. `send` delivers a session update of the prompt's session; it must not
- * throw, and must deliver updates in the order it is called, also relative to
- * the agent's own updates.
+ * in, with the id of the user message it became. `send` delivers a session
+ * update of the prompt's session; it must not throw, and must deliver updates
+ * in the order it is called, also relative to the agent's own updates.
 *
- * - Taken in: the prompt's `user_message`, then `running`, then the answer.
- * - Waiting on a permission request or a question: `requires_action`, and
- *   `running` once none is open.
- * - Ended: `idle` with the stop reason, usage, and `_meta` of the turn.
- * - Failed after it was taken in: `idle` with the `error` stop reason and the
- *   JSON-RPC error that v1 answers the prompt with, so a client can show its
- *   message and handle its code as for an error response (for example,
- *   `-32000` starts the client's sign-in).
+ * - Taken in: the prompt's `user_message`, then the answer. From then on, the
+ *   turn is the session's foreground work, which reports its states (see
+ *   {@link v2Foreground}).
 * - Ended or failed before it was taken in: the answer is a JSON-RPC error,
 *   `-32800` for a prompt that a cancel ended in the queue.
- *
- * Deferred decision: a turn whose background subagents still run ends only
- * when they finish (`Turn.deferredSettle`), so `idle` waits for them too. The
- * hold exists for v1, whose clients stop listening at the prompt response.
- * v2 allows background updates while idle, so it could report `idle` at the
- * turn's result instead, with a turn event for the hold. To be decided with
- * async tasks (step 6 in `docs/acp-v2.md`).
 */
 export function v2Prompt(
  agent: ClaudeAcpAgent,
@@ -50,40 +38,21 @@ export function v2Prompt(
      inserted(messageId) {
        inserted = true;
        send({ sessionUpdate: "user_message", messageId, content: params.prompt });
-        send({ sessionUpdate: "state_update", state: "running" });
        resolve({ messageId });
      },
-      awaitingUser() {
-        send({ sessionUpdate: "state_update", state: "requires_action" });
-      },
-      resumed() {
-        send({ sessionUpdate: "state_update", state: "running" });
-      },
      ended(outcome) {
-        if (inserted) {
-          send(idle(outcome));
-        } else if (outcome.stopReason === "cancelled") {
-          reject(RequestError.requestCancelled());
-        } else {
-          reject(
-            RequestError.internalError(
-              { stopReason: outcome.stopReason },
-              "The turn ended before Claude Code took the prompt in",
-            ),
-          );
-        }
+        if (inserted) return;
+        reject(
+          outcome.stopReason === "cancelled"
+            ? RequestError.requestCancelled()
+            : RequestError.internalError(
+                { stopReason: outcome.stopReason },
+                "The turn ended before Claude Code took the prompt in",
+              ),
+        );
      },
      failed(error) {
-        if (!inserted) {
-          reject(error);
-          return;
-        }
-        send({
-          sessionUpdate: "state_update",
-          state: "idle",
-          stopReason: "error",
-          error: jsonRpcError(error),
-        });
+        if (!inserted) reject(error);
      },
    };
    let request: PromptRequest;
@@ -97,6 +66,49 @@ export function v2Prompt(
  });
 }

+/**
+ * Reports the foreground work of a session (see {@link ForegroundEvents}) as
+ * its `state_update`s. `send` delivers a session update of that session, as
+ * for {@link v2Prompt}.
+ *
+ * - Started: `running`. For a prompt's turn, right after its `user_message`.
+ * - Waiting on a permission request or a question: `requires_action`, and
+ *   `running` once none is open.
+ * - Ended: `idle` with the stop reason, usage, and `_meta` of the work.
+ * - Failed: `idle` with the `error` stop reason and the JSON-RPC error that v1
+ *   answers the prompt with, so a client can show its message and handle its
+ *   code as for an error response (for example, `-32000` starts the client's
+ *   sign-in).
+ *
+ * The work is a prompt's turn or a model cycle that Claude Code started on its
+ * own, such as its follow-up after a background subagent finished. A turn's
+ * work ends at its result, also when v1 holds the turn's answer for the
+ * background subagents it spawned (`Turn.deferredSettle`): v2 allows
+ * background updates while idle, so the subagents' output and requests arrive
+ * after `idle`, and their follow-up is a cycle of its own.
+ */
+export function v2Foreground(send: (update: v2.SessionUpdate) => void): ForegroundEvents {
+  return {
+    running() {
+      send({ sessionUpdate: "state_update", state: "running" });
+    },
+    awaitingUser() {
+      send({ sessionUpdate: "state_update", state: "requires_action" });
+    },
+    ended(outcome) {
+      send(idle(outcome));
+    },
+    failed(error) {
+      send({
+        sessionUpdate: "state_update",
+        state: "idle",
+        stopReason: "error",
+        error: jsonRpcError(error),
+      });
+    },
+  };
+}
+
 /** The JSON-RPC error that v1 answers a failed prompt with. */
 function jsonRpcError(error: unknown): { code: number; message: string; data?: unknown } {
  if (error instanceof RequestError) {
--- a/src/v2/session-update.ts
+++ b/src/v2/session-update.ts
@@ -55,6 +55,10 @@ export function v2SessionUpdate(
        plan: { type: "items", planId: SESSION_PLAN_ID, entries: update.entries },
        ...(update._meta != null ? { _meta: update._meta } : {}),
      };
+    case "plan_update":
+    case "plan_removed":
+      // v1's draft plan operations have v2's shape.
+      return update;
    case "current_mode_update":
      // v2 has no modes: the mode is the `mode` config option. Every mode
      // change also reaches the client as a `config_option_update` or in the
--- a/src/v2/session.ts
+++ b/src/v2/session.ts
@@ -60,28 +60,12 @@ export function v1RestoreSessionRequest(
 }

 /**
- * The v1 requests that a v2 `session/fork` means.
- *
- * The agent's v1 fork copies the transcript into a new session and returns
- * only its id; a v1 client then resumes or loads it. A v2 fork returns the new
- * session with its config options, like `session/new`, so the client can
- * prompt it. The v2 surface therefore forks, then resumes the fork without
- * replay, with the request's `cwd`, `additionalDirectories`, and
- * `mcpServers`. The request's `_meta` goes to the fork alone.
+ * The v1 request of a v2 `session/fork`. In both versions the agent's fork
+ * returns a session that the client can prompt, with its config options.
 */
-export function v1ForkSessionRequests(params: v2.ForkSessionRequest): {
-  fork: ForkSessionRequest;
-  resume: (sessionId: string) => ResumeSessionRequest;
-} {
-  const { mcpServers, _meta, ...request } = params;
-  const session = {
-    ...request,
-    ...(mcpServers ? { mcpServers: mcpServers.map(v1McpServer) } : {}),
-  };
-  return {
-    fork: { ...session, ...(_meta != null ? { _meta } : {}) },
-    resume: (sessionId) => ({ ...session, sessionId }),
-  };
+export function v1ForkSessionRequest(params: v2.ForkSessionRequest): ForkSessionRequest {
+  const { mcpServers, ...request } = params;
+  return { ...request, ...(mcpServers ? { mcpServers: mcpServers.map(v1McpServer) } : {}) };
 }

 /** v2 drops `modes`: the session mode is the `mode` config option, which the agent always lists. */
--- a/src/v2/tool-call-meta.ts
+++ b/src/v2/tool-call-meta.ts
@@ -0,0 +1,104 @@
+/**
+ * The `_meta` of the tool calls of one ACP v2 connection, as the client stores
+ * it.
+ *
+ * The agent gives each v1 tool call report the `_meta` keys of that report.
+ * An AIR client merges them by key (see `ToolCallFieldTracker`), and another
+ * v1 client reads them per report. A v2 client stores a tool call's `_meta`,
+ * and a report that carries `_meta` replaces it. So the earlier keys must
+ * travel again, or the `{ toolName }` of a tool's result would replace, for
+ * example, the reason of the denial before it.
+ *
+ * {@link V2ToolCallMeta} therefore keeps the merged `_meta` of each tool call,
+ * with the `claudeCode` keys merged one by one and every other key replaced
+ * whole, as `ToolCallFieldTracker` models it. A report that changes it carries
+ * all of it; a report that changes nothing carries no `_meta`.
+ *
+ * `claudeCode.toolName` repeats the name of the tool, which v2 has a field
+ * for. It becomes the `name` of a tool call that has none yet, and is left out
+ * of the stored `_meta`. Subagent routing reads it before this, on the agent's
+ * v1 reports.
+ */
+import type { ToolCall, ToolCallUpdate } from "@agentclientprotocol/sdk";
+
+type Meta = Record<string, unknown>;
+
+/** The number of tool calls whose `_meta` a connection remembers. */
+const TOOL_CALL_LIMIT = 2048;
+
+export class V2ToolCallMeta {
+  /** The stored `_meta` of each tool call, by session and tool call, oldest first. */
+  private readonly calls = new Map<string, { meta: Meta; named: boolean }>();
+
+  /**
+   * `report` with the tool call's whole `_meta` when the report changes it,
+   * without `_meta` when it does not, and with `name` when it names the tool
+   * call for the first time. `starts` says that the report starts the tool
+   * call (a v1 `tool_call`), which forgets what an earlier one stored.
+   */
+  apply<Report extends ToolCall | ToolCallUpdate>(
+    sessionId: string,
+    report: Report,
+    starts: boolean,
+  ): Report {
+    const key = `${sessionId} ${report.toolCallId}`;
+    const call = (!starts && this.calls.get(key)) || { meta: {}, named: false };
+    this.remember(key, call);
+
+    const { _meta, ...fields } = report;
+    const result = fields as Report;
+    const { toolName, ...claudeCode } = asRecord(_meta?.claudeCode) ?? {};
+    if (report.name != null) {
+      call.named = true;
+    } else if (!call.named && typeof toolName === "string") {
+      result.name = toolName;
+      call.named = true;
+    }
+
+    const meta: Meta = { ...call.meta };
+    for (const [name, value] of Object.entries(_meta ?? {})) {
+      if (name !== "claudeCode") meta[name] = value;
+    }
+    if (Object.keys(claudeCode).length > 0) {
+      meta.claudeCode = { ...asRecord(call.meta.claudeCode), ...claudeCode };
+    }
+    if (JSON.stringify(meta) !== JSON.stringify(call.meta)) {
+      call.meta = meta;
+      result._meta = meta;
+    }
+    return result;
+  }
+
+  /**
+   * The tool call of a permission request's subject: like {@link apply}, but
+   * with the tool call's whole `_meta` even when the subject changes nothing,
+   * since a client can show the request from the request alone.
+   */
+  subject<Report extends ToolCall | ToolCallUpdate>(sessionId: string, toolCall: Report): Report {
+    const result = this.apply(sessionId, toolCall, false);
+    const stored = this.calls.get(`${sessionId} ${toolCall.toolCallId}`)?.meta ?? {};
+    if (result._meta === undefined && Object.keys(stored).length > 0) result._meta = stored;
+    return result;
+  }
+
+  /** Forgets the tool calls of a session, when it closes. */
+  forget(sessionId: string): void {
+    for (const key of this.calls.keys()) {
+      if (key.startsWith(`${sessionId} `)) this.calls.delete(key);
+    }
+  }
+
+  /** Stores the entry as the most recent one, and forgets the oldest one past the limit. */
+  private remember(key: string, call: { meta: Meta; named: boolean }): void {
+    this.calls.delete(key);
+    this.calls.set(key, call);
+    if (this.calls.size > TOOL_CALL_LIMIT) {
+      const oldest = this.calls.keys().next().value;
+      if (oldest !== undefined) this.calls.delete(oldest);
+    }
+  }
+}
+
+function asRecord(value: unknown): Meta | undefined {
+  return value && typeof value === "object" && !Array.isArray(value) ? (value as Meta) : undefined;
+}