Composer 1 agent edits files in Plan Mode instead of only proposing a plan

[bastienlimbour (Bastien Limbour Pruvost)]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

When using the Composer 1 model in Plan Mode, the agent unexpectedly starts editing project files. In Plan Mode, the agent should limit itself to generating a plan and wait for explicit confirmation before performing any modifications. Instead, it proceeds with edits as if it were in Agent Mode. This behavior defeats the purpose of Plan Mode and risks unintended changes to the codebase.

Steps to Reproduce

1. Open a project in Cursor.
2. Switch to Plan Mode.
3. Select the Composer 1 model.
4. Ask the agent to propose a plan for changes (e.g., refactoring a file or adding a feature).
5. Observe the agent’s actions.

Expected Behavior

In Plan Mode, the agent should:
• Only generate a plan outlining the proposed steps.
• Avoid editing any files.
• Wait for the user to switch to Agent Mode and explicitly approve the execution of the plan.

Operating System

MacOS

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.0.77
VSCode Version: 1.99.3
Commit: ba90f2f88e4911312761abab9492c42442117cf0
Date: 2025-11-13T23:10:43.113Z
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Darwin arm64 24.6.0

For AI issues: which model did you use?

Composer 1

For AI issues: add Request ID with privacy disabled

5fbc9066-64d9-48a4-b052-7da3e947c9fb

Does this stop you from using Cursor

No - Cursor works, but with this issue

Screenshot

On the screenshot we can see the Plan Mode and the 4 files edited.

[deanrie]

Hey, thanks for the report. You’re absolutely right, Plan Mode should first create a plan and only then execute it. Right now it’s jumping straight to implementation, which is apparently a bug.

Your specific issue (skipping plan approval with Composer 1) is a variant of this broader Plan Mode problem. I’ll pass your report to the team.

Could you also confirm if the same thing happens with other models, for example Claude Sonnet 4.5?

[bastienlimbour (Bastien Limbour Pruvost)]

For now I’ve only encountered this bug with Composer 1.
The other models seemed to understand from the prompt that they only needed to produce a plan, so they didn’t even try to modify any files.