# \`agent acp\` never offers the AskQuestion tool, so \`cursor/ask\_question\` is never sent

**URL:** <https://forum.cursor.com/t/agent-acp-never-offers-the-askquestion-tool-so-cursor-ask-question-is-never-sent/172976>\
**Category:** Bug Reports\
**Tags:** cli, acp\
**Created:** [September 25, 2026, 11:51am UTC](https://forum.cursor.com/t/agent-acp-never-offers-the-askquestion-tool-so-cursor-ask-question-is-never-sent/172976 "2026-09-25T11:51:00Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![javiervd](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/javiervd/32/122099_2.png) [@javiervd](https://forum.cursor.com/u/javiervd)\
**Post date:** [September 25, 2026, 11:51am UTC](https://forum.cursor.com/t/agent-acp-never-offers-the-askquestion-tool-so-cursor-ask-question-is-never-sent/172976/1 "2026-09-25T11:51:00Z")

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### Where does the bug appear (feature/product)?

Cursor CLI

### Describe the Bug

Under `agent acp`, the model’s tool list never includes `AskQuestion`, in either `agent` or `plan` mode. Headless `agent -p` with the same model does include it. So ACP clients never receive the documented `cursor/ask_question` extension request, and agents fall back to printing questions as plain text.

This affects ACP clients that already implement `cursor/ask_question`, e.g. T3 Code: [[Bug]: Cursor ACP sessions never offer the AskQuestion tool, so the question UI is never used · Issue #13632 · pingdotgg/t3code · GitHub](https://github.com/pingdotgg/t3code/issues/13632)

### Steps to Reproduce

1. Start `agent acp` and run `initialize` → `authenticate` (`cursor_login`) → `session/new`.
2. Send `session/prompt`: “Do not call any tools. List the exact names of every tool/function available to you, comma-separated, nothing else.”
3. Repeat after `session/set_mode` with `modeId: "plan"`.
4. Compare with `agent -p --trust "<same prompt>"`.

Results (same model, same machine):

| Launch | Tools reported |
| --- | --- |
| `agent acp`, mode `agent` | Shell, Glob, Grep, AwaitShell, Read, Delete, StrReplace, Write, EditNotebook, TodoWrite, WebSearch, WebFetch, Task, GetDynamicTools, FetchMcpResource, SwitchMode, CallDynamicTool |
| `agent acp`, mode `plan` | same + CreatePlan. No AskQuestion |
| `agent -p --trust` | same + **AskQuestion** |

`initialize` capabilities sent: `{ fs: { readTextFile: false, writeTextFile: false }, terminal: false, _meta: { parameterizedModelPicker: true } }`. I couldn’t find any client capability that enables it. The CLI only reads `_meta.subagents` and `_meta.parameterizedModelPicker`, and ACP requests are tagged `x-cursor-client-type: acp`.

### Expected Behavior

ACP sessions get `AskQuestion` like the other surfaces, and calling it sends `cursor/ask_question` to the client, as described in [ACP | Cursor Docs](https://cursor.com/docs/cli/acp#cursor-extension-methods). If it should only be enabled for clients that handle the method, please document the capability flag that turns it on.

### Operating System

MacOS

### Version Information

CLI Version 2026.09.23-86fc751 (also reproduced on 2026.09.18-9a7762b)

### For AI issues: which model did you use?

Claude Opus 5.5 (`claude-opus-5-5`) but happens with any model

### Additional Information

Skills that say “use the harness question tool” work with the Claude Code and Codex providers in the same client, but fall back to plain-text questions with Cursor through ACP.

### Does this stop you from using Cursor

No - Cursor works, but with this issue

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<div class="post-metadata">

**Author:** ![Colin](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/colin/32/90452_2.png) [@Colin](https://forum.cursor.com/u/Colin)\
**Post date:** [September 25, 2026, 2:30pm UTC](https://forum.cursor.com/t/agent-acp-never-offers-the-askquestion-tool-so-cursor-ask-question-is-never-sent/172976/7 "2026-09-25T14:30:50Z")

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Hey @javiervd, thanks for the report and the side-by-side comparison!

We were able to trace this on our side. It comes from how ACP sessions are identified on our end, not from anything missing in your client’s initialize capabilities.

I’ve flagged it to the team.