Claude Code incorrectly reverted user's uncommitted work while debugging

Issue

Claude Code ran git checkout -- . to revert uncommitted changes without stashing them first, resulting in permanent loss of user's work.

What happened

1. User had uncommitted frontend changes (~1 day of work)
2. Application had a rendering issue
3. Claude assumed frontend changes were the cause and ran git checkout -- .
4. Claude did NOT stash the changes first
5. The actual root cause was a backend API bug (unrelated to the frontend changes)
6. User's uncommitted work was permanently lost

Expected behavior

Claude should:

1. Always use git stash before reverting uncommitted changes
2. Investigate all potential causes before assuming the user's recent work is the problem
3. Never permanently delete uncommitted work

Impact

• Significant development work permanently lost
• Changes cannot be recovered

Session details

• Model: claude-opus-4-5-20251101
• Date: 2026-01-02