🧙 Git Gandalf

The Local (or Remote) LLM–Powered Pre-Commit Code Reviewer

Git Gandalf is a "boring", dependency-free git hook that blocks high-risk commits (like hardcoded secrets) using an LLM. It is designed for Local LLMs (like LM Studio) but can be configured to point anywhere.

Prerequisites

1. Node.js: Version 18+ (required for built-in fetch).
2. An LLM Endpoint:

• Default: Local server running at http://127.0.0.1:1234 (e.g., LM Studio, Ollama via compatibility mode).
• Custom: You can edit the script to point to any OpenAI-compatible endpoint.

Installation

1. Copy the Script

Copy the bin/gitgandalf.js file to the root of your project (the same folder as your package.json).

2. Install the Hook

Copy the pre-commit file to your .git hooks folder:

cp hooks/pre-commit .git/hooks/pre-commit

3. Grant Permissions (⚠️ Required)

Git will not run the script unless you explicitly make it executable. If you skip this, you will get a "Permission Denied" error.

Mac / Linux / Git Bash:

chmod +x .git/hooks/pre-commit

Windows (PowerShell): Usually not required, but if you run into issues, ensure your user has execute rights on the file.

Configuration (Switching to Online/Remote LLMs)

By default, Git Gandalf looks for a local server. To change this:

1. Open gitgandalf.js in your editor.
2. Edit the BASE_URL constant at the top:

// CHANGE THIS:
const BASE_URL = "http://127.0.0.1:1234";

// TO YOUR SERVER (example):
const BASE_URL = "https://my-internal-llm.company.com";

(Note: The current version does not support Authorization headers for paid APIs like OpenAI/Anthropic out of the box. You must modify the fetch call in the script to add API keys if needed.)

Usage

Just commit as normal!

git add .
git commit -m "feat: new login page"

• 🟢 ALLOW: Commit proceeds.
• 🟡 WARN: Commit proceeds, but you get a warning.
• 🔴 BLOCK: Commit fails. Fix the issues and try again.

Emergency Bypass

If the LLM is down, hallucinating, or blocking a critical hotfix, you can skip the hook:

git commit -m "critical fix" --no-verify

Troubleshooting

• Permission denied: You forgot to run chmod +x .git/hooks/pre-commit.
• Git Gandalf Skipped: The script couldn't reach the URL defined in BASE_URL. Check if your model is running.