[MODEL] opus

Preflight Checklist

• [x] I have searched existing issues for similar behavior reports
• [x] This report does NOT contain sensitive information (API keys, passwords, etc.)

Type of Behavior Issue

Claude accessed files outside the working directory

What You Asked Claude to Do

I asked Claude to fix a bug with an incompatibility with a library header and it modified the library header instead of fixing my own code.

What Claude Actually Did

Claude modified <string.h> in mingw64 installation

Expected Behavior

Claude should have treated system includes as immutable

Files Affected

<string.h>

Permission Mode

Accept Edits was ON (auto-accepting changes)

Can You Reproduce This?

Haven't tried to reproduce

Steps to Reproduce

Claude Model

Opus

Relevant Conversation

This is a tricky one, the easiest thing is to modify the system header. What it actually needed was some -Da=b arguments on the compile command line.

Impact

Medium - Extra work to undo changes

Claude Code Version

latest

Platform

Anthropic API

Additional Context

It happens if several attempts to resolve the compilation error are unsuccessful