Git Guardrails Claude Code

---
name: git-guardrails-claude-code
description: >-
  Installs Claude Code PreToolUse safeguards against destructive Git commands; use to protect
  repositories, not for general Git workflow guidance.
allowed-tools: Read Grep Glob Bash Write Edit
compatibility: >
  Claude Code only — uses Claude Code's PreToolUse hook system. Can be installed
  per-project (.claude/hooks/) or globally (~/.claude/hooks/). Pairs with git-workflow
  for safe branching practices.
metadata:
  tags: git, safety, hooks, destructive-operations, guardrails, claude-code
  platforms: Claude
  version: "1.0"
  source: mattpocock/skills
---

# Git Guardrails for Claude Code

Prevent Claude Code from executing destructive git operations via PreToolUse hooks.

## When to use this skill

- Protecting critical repositories from accidental destructive git commands
- Setting up safety nets before giving Claude Code broad git permissions
- After an incident involving unintended git destructive operations

## When not to use this skill

- General git workflow guidance → use `git-workflow`
- Non-Claude-Code platforms → hooks are Claude Code-specific

## Blocked operations

The guardrail blocks:
- `git push --force` / `git push -f`
- `git reset --hard`
- `git clean -f` / `git clean -fd`
- `git branch -D`
- `git checkout -- .` / `git checkout -- <file>`
- `git restore` (destructive forms)

## Installation

### Step 1 — Choose scope

**Project-level** (recommended for critical repos):
```bash
mkdir -p .claude/hooks
```

**Global** (for all Claude Code sessions):
```bash
mkdir -p ~/.claude/hooks
```

### Step 2 — Create the blocking script

Save as `.claude/hooks/git-guardrails.sh` (or `~/.claude/hooks/git-guardrails.sh`):

```bash
#!/bin/bash
# Blocks destructive git operations

COMMAND="$1"

if echo "$COMMAND" | grep -qE 'git (push --force|push -f|reset --hard|clean -f|clean -fd|branch -D|checkout -- |restore )'; then
  echo "BLOCKED: Claude does not have authority to run destructive git operations."
  echo "Command attempted: $COMMAND"
  echo "If you need this operation, run it yourself in the terminal."
  exit 2
fi

exit 0
```

```bash
chmod +x .claude/hooks/git-guardrails.sh
```

### Step 3 — Register the hook in settings

Add to `.claude/settings.json` (project) or `~/.claude/settings.json` (global):

```json
{
  "hooks": {
    "PreToolUse": [
      {
        "matcher": "Bash",
        "hooks": [
          {
            "type": "command",
            "command": ".claude/hooks/git-guardrails.sh"
          }
        ]
      }
    ]
  }
}
```

For global installation, use the full path: `~/.claude/hooks/git-guardrails.sh`

### Step 4 — Verify

```bash
echo "git reset --hard" | .claude/hooks/git-guardrails.sh
# Should exit with status 2 and print BLOCKED message
```

## Customization

Edit the regex pattern in the script to add or remove blocked operations:

```bash
# Add git tag -d to blocked list:
grep -qE 'git (push --force|push -f|reset --hard|clean -f|clean -fd|branch -D|checkout -- |restore |tag -d)'
```

## Instructions
1. Identify the task trigger and expected output.
2. Follow the workflow steps in this skill from top to bottom.
3. Validate outputs before moving to the next step.
4. Capture blockers and fallback path if any step fails.

## Examples
- Example: Apply this skill to a small scope first, then scale to full scope after validation passes.

## Best practices
- Keep outputs deterministic and auditable.
- Prefer small reversible changes over broad risky edits.
- Record assumptions explicitly.

## References
- Project standards: `.agent-skills/skill-standardization/SKILL.md`
- Validator script: `.agent-skills/skill-standardization/scripts/validate_skill.sh`