[BUG] Claude Code modifies code without being asked

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?

I asked Claude to explain issues in my code (not to fix them),
but it went ahead and modified the files on its own without any
explicit request to do so.

Steps to reproduce:

1. Ask Claude to explain a bug ("3 설명, 4 설명")
2. Claude automatically edits the files without being asked

Expected behavior: Only explain the issues
Actual behavior: Modifies code without permission

What Should Happen?

Claude should only perform actions that are explicitly requested by the user.
When asked to "explain" something, Claude should provide an explanation only,
without making any code changes.

Error Messages/Logs

Steps to Reproduce

1. Ask Claude to explain specific issues found in the code

(e.g. "explain issue 3, explain issue 4")

1. Claude explains the issues but also modifies the code files

without any instruction to do so

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

unknown

Claude Code Version

2.1.173

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

VS Code integrated terminal

Additional Information

<img width="730" height="635" alt="Image" src="https://github.com/user-attachments/assets/791312a2-99cd-4ba9-9ab5-f3933827b1b2" />