Git Guardrails Claude Code

Git guardrails for Claude Code

Wire up a PreToolUse hook that inspects every Bash command Claude is about to run and refuses the destructive git operations before they touch the repository.

What the guard refuses

• git push in any form, including --force
• git reset --hard
• git clean -f and git clean -fd
• git branch -D
• git checkout . and git restore .

When a command matches, the hook exits with code 2 and Claude receives a message stating it is not permitted to run that command, so it stops rather than retrying.

Steps

1. Confirm the scope

Ask whether the guard should cover this project only (.claude/settings.json) or every project (~/.claude/settings.json). The answer decides where the script and the hook entry go.

2. Place the hook script

The bundled script lives at [scripts/block-dangerous-git.sh](scripts/block-dangerous-git.sh). Copy it to match the chosen scope:

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

Then mark it executable with chmod +x.

3. Register the hook in settings

Add the hook to the settings file for the chosen scope.

Project (.claude/settings.json):

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

Global (~/.claude/settings.json):

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

When the settings file already exists, merge this entry into the existing hooks.PreToolUse array and leave the rest of the file untouched.

4. Offer to tune the pattern list

Ask whether any patterns should be added or dropped, then edit the DANGEROUS_PATTERNS array in the copied script to match.

5. Confirm it works

Feed a sample command through the script and check the result:

echo '{"tool_input":{"command":"git push origin main"}}' | 

A working guard exits with code 2 and prints a BLOCKED line to stderr.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: officialunofficial
• Source: officialunofficial/skills
• License: Apache-2.0

Install and usage instructions live in the source repository linked above.