setup-git-guardrails

Setup Git Guardrails

Install a Claude Code hook that intercepts dangerous git commands before they execute. The hook runs as a PreToolUse event on the Bash tool and blocks commands that could destroy work.

Step 1: Choose Scope

Ask the user:

Install git guardrails for this project only or globally?

• Project: adds to .claude/settings.local.json in this repo
• Global: adds to ~/.claude/settings.json for all repos

Step 2: Install the Hook Script

Copy the block-dangerous-git.sh script to the appropriate location:

• Project scope: .claude/hooks/block-dangerous-git.sh
• Global scope: ~/.claude/hooks/block-dangerous-git.sh

Make it executable: chmod +x.

Step 3: Register the Hook

Add the hook to the chosen settings file:

{
  "hooks": {
    "PreToolUse": [
      {
        "matcher": "Bash",
        "hooks": [
          {
            "type": "command",
            "command": "{path}/block-dangerous-git.sh"
          }
        ]
      }
    ]
  }
}

If hooks already exist in the settings file, merge -- don't overwrite.

Step 4: Customise (optional)

Present the default blocked patterns:

Blocked commands:

• git push (any form)
• git reset --hard
• git clean -f / git clean -fd
• git branch -D
• git checkout .
• git restore .

Want to add or remove any patterns?

If the user wants changes, edit the script accordingly.

Step 5: Verify

1. Attempt a blocked command (e.g. git push --dry-run) and confirm it's intercepted
2. Attempt a safe command (e.g. git status) and confirm it passes

Report that guardrails are active.