[BUG] Claude Code: code-review skill auto-merges PRs despite "no merge" instructions

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

• Problem: In code review workflows, Claude consistently merge PRs without explicit user authorization, even when told "no merge" and "only approve"
• Pattern: Happens every review session; user has to correct me repeatedly
• Impact: Causes unwanted commits to main, triggers CI/CD, breaks audit trail
• Root cause: Claude apparently treat "approve" as "merge" and don't respect read-only boundaries
• Request: Fix the instruction layer so code-review agents refuse to merge unless explicitly asked with clear language like "merge this PR"

What Should Happen?

When in code review, Claude should not make any code changes and should not trigger any merges.

Error Messages/Logs

Steps to Reproduce

Do a code review using Claude of any PR
After approval, often Claude will ask to merge.
This time, it merged without asking, when asked to approve the PR

Claude Model

Other

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.236 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

<img width="1840" height="426" alt="Image" src="https://github.com/user-attachments/assets/90f93f98-60be-4988-8c59-2f1f9234f106" />

<img width="4092" height="1330" alt="Image" src="https://github.com/user-attachments/assets/91a191fa-1882-4496-b8e9-e7bb18baa09d" />