[BUG] Claude is unaware of case-insensitive filesystems and uses unsafe rm -rf on user data

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?

When working on an exFAT USB drive, Claude attempted to create a directory with a different case (Content) while a directory with the same name (content) already existed. Since exFAT is case-insensitive, these resolved to the same path. Claude did not detect this and later ran rm -rf on the directory, permanently deleting all user data.

Issues:

Claude does not check filesystem case-sensitivity before creating directories that differ only in case
Claude uses rm -rf (irreversible) instead of safer alternatives like moving to trash
Claude does not verify source and destination are independent paths before deleting source data

What Should Happen?

Claude should check filesystem case-sensitivity before creating directories and should never use rm -rf on user data without verifying path independence first.

Error Messages/Logs

Steps to Reproduce

Work on an exFAT USB drive that has a folder named content
Ask Claude to create a folder named Content on the same drive
Ask Claude to delete the old content folder

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

4.6

Claude Code Version

4.6

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_