Setup Git Guardrails

Sets up a PreToolUse hook that intercepts and blocks dangerous git commands before Claude executes them.

What Gets Blocked

• git push (all variants including --force)
• git reset --hard
• git clean -f / git clean -fd
• git branch -D
• git checkout . / git restore .

When blocked, Claude sees a message telling it that it does not have authority to access these commands.

Steps

1. Ask scope

Ask the user: install for this project only (.claude/settings.json) or all projects (~/.claude/settings.json)?

2. Copy the hook script

Copy the bundled script to the target location based on scope and make it executable with chmod +x.

3. Add hook to settings

Add the hook to the appropriate settings file, merging into existing hooks.PreToolUse array if needed.

4. Ask about customization

Ask if user wants to add or remove any patterns from the blocked list.

5. Verify

Run a quick test:

echo '{"tool_input":{"command":"git push origin main"}}' | /path/to/script

Should exit with code 2 and print a BLOCKED message to stderr.