refactor: stop advertising steering on the experimental ACP v2 surface (#1254)

Found while reviewing what's left of opt-in ACP v2 support. Nothing
changes on ACP v1.

## Problem

The agent advertises `_session/steering` in the top-level `_meta` of its
v1 `initialize` response (`steering: { supported: true }`), and the v2
handshake passed that `_meta` through. The v2 surface doesn't register
`_session/steering`, so a v2 client that steered got "method not found".

## Change

The v2 `initialize` response leaves out the top-level `_meta` keys that
advertise an extension the v2 surface doesn't serve
(`UNSERVED_EXTENSION_KEYS` in `src/v2/initialize.ts`), which is
`steering` alone today. That sits next to the existing rule that keeps
the unstable `providers` capability unadvertised.

Whether v2 serves steering is left to the plan for the unstable and
extension surfaces. The protocol has no steering RFD yet, and steering
may need a different design on v2, which answers a prompt as soon as
it's accepted.

## Verification

- The handshake test checks that the v2 response has no
`_meta.steering`. The v1 handshake tests still check that v1 advertises
it.
- Every v2 golden file changes on its `initialize` line only. The line
loses its `_meta` and is otherwise identical.
- Build, lint and all 2409 tests pass.

src/tests/acp-scenarios/__snapshots__/v2/ask-user-question.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/async-task-ends-before-tool-id.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/async-task-held-until-tool-id.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/async-task-released-at-turn-end.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/bash-background.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/bash-error.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/bash-foreground.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/compaction-failed-legacy.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/compaction-legacy.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/compaction-update.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/edit-rejected.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/edit-with-permission.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/exit-plan-approve.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/exit-plan-reject.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/goal.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"/goal Ship the feature","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/grep-and-glob.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/mcp-tool.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/memory-recall.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/network-permission.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/notebook-edit.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/permission-denied.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/rate-limit-and-origin.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/read.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/session-load-replay.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"messageId":"00000000-0000-4000-8000-00000000c001","sessionUpdate":"user_message"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":{"text":"Fix the bug","type":"text"},"messageId":"00000000-0000-4000-8000-00000000c001","sessionUpdate":"user_message_chunk"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[],"messageId":"msg_r1","sessionUpdate":"agent_thought"}}}

src/tests/acp-scenarios/__snapshots__/v2/session-setup.jsonl

@@ -1,3 +1,3 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}

src/tests/acp-scenarios/__snapshots__/v2/skill.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/subagent-agent-async.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/subagent-late-child-update.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/subagent-native-sessions.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/subagent-nested.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/subagent-task-legacy.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/subagent-transcript-extension.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/task-create-update.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/task-output-and-stop.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/text-and-thinking.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/todo-write.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/tool-progress.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/web-fetch-and-search.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/write-existing.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-scenarios/__snapshots__/v2/write-new.jsonl

@@ -1,4 +1,4 @@
-{"kind":"response","method":"initialize","payload":{"_meta":{"steering":{"supported":true}},"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
+{"kind":"response","method":"initialize","payload":{"authMethods":[],"capabilities":{"_meta":{"authStatus":{},"claudeCode":{"promptQueueing":true}},"session":{"additionalDirectories":{},"delete":{},"mcp":{"http":{},"stdio":{}},"prompt":{"embeddedContext":{},"image":{}}}},"info":{"name":"@agentclientprotocol/claude-agent-acp","title":"Claude Agent","version":"<version>"},"protocolVersion":2}}
 {"kind":"response","method":"session/new","payload":{"configOptions":[{"category":"mode","configId":"mode","currentValue":"default","description":"Session permission mode","name":"Mode","options":[{"description":"Always ask before making changes","name":"Manual","value":"default"},{"description":"Automatically accept all file edits","name":"Accept edits","value":"acceptEdits"},{"description":"Create a plan before making changes","name":"Plan","value":"plan"},{"description":"Claude handles permission decisions","name":"Auto","value":"auto"},{"description":"Accepts all permissions","name":"Bypass permissions","value":"bypassPermissions"}],"type":"select"},{"category":"model","configId":"model","currentValue":"claude-sonnet-4-6","description":"AI model to use","name":"Model","options":[{"description":"Fast","name":"Claude Sonnet 4.6","value":"claude-sonnet-4-6"}],"type":"select"}],"sessionId":"<session>"}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"availableCommands":[{"description":"Show the MCP servers and their status, or reconnect, enable, or disable a server","input":{"hint":"[reconnect|enable|disable [<server>|all]]","type":"text"},"name":"mcp"}],"sessionUpdate":"available_commands_update"}}}
 {"kind":"notification","method":"session/update","payload":{"sessionId":"<session>","update":{"content":[{"text":"prompt 1","type":"text"}],"messageId":"<id-1>","sessionUpdate":"user_message"}}}

src/tests/acp-v2.test.ts

@@ -285,6 +285,8 @@ describe("ACP protocol routing", () => {
       additionalDirectories: {},
     });
     expect(response.capabilities?.providers).toBeUndefined();
+    // Nor `_session/steering`, which v1 advertises in the top-level `_meta`.
+    expect(response._meta?.steering).toBeUndefined();
     expect(response.authMethods?.length).toBeGreaterThan(0);
     for (const method of response.authMethods ?? []) {
       expect(method).not.toHaveProperty("id");

src/v2/initialize.ts

@@ -44,17 +44,27 @@ export function v1InitializeRequest(request: v2.InitializeRequest): InitializeRe
   };
 }
 
+/**
+ * The top-level `_meta` keys of the agent's v1 `initialize` response that
+ * advertise an extension the v2 surface does not serve yet: `steering`, for
+ * `_session/steering`.
+ */
+const UNSERVED_EXTENSION_KEYS: readonly string[] = ["steering"];
+
 /**
  * The v2 `initialize` response for the v1 response of the agent.
  *
- * It does not advertise the unstable `providers` methods, which the v2
- * surface does not serve yet.
+ * It does not advertise what the v2 surface does not serve yet: the unstable
+ * `providers` methods, and the extensions of {@link UNSERVED_EXTENSION_KEYS}.
  */
 export function v2InitializeResponse(response: InitializeResponse): v2.InitializeResponse {
   if (!response.agentInfo) {
     throw new Error("ACP v2 requires agentInfo, and the agent reported none");
   }
   const meta = response.agentCapabilities?._meta;
+  const topMeta = Object.fromEntries(
+    Object.entries(response._meta ?? {}).filter(([key]) => !UNSERVED_EXTENSION_KEYS.includes(key)),
+  );
   return {
     protocolVersion: v2.PROTOCOL_VERSION,
     info: response.agentInfo,
@@ -65,7 +75,7 @@ export function v2InitializeResponse(response: InitializeResponse): v2.Initializ
       ...(meta != null ? { _meta: meta } : {}),
     },
     authMethods: (response.authMethods ?? []).map(v2AuthMethod),
-    ...(response._meta != null ? { _meta: response._meta } : {}),
+    ...(Object.keys(topMeta).length > 0 ? { _meta: topMeta } : {}),
   };
 }