gcm — Generate Commit Message

AI-powered git commit message generator. Reads your staged diff, understands your changes, and writes a senior-level conventional commit message — not just the filename, the actual intent.

Install

npm install -g gcm-agent

First Run

The first time you run gcm, it automatically walks you through setup in the terminal — no manual config needed:

┌  Welcome to gcm! Let's get you set up.
│
◆  Pick a provider
│  ● Groq          (free)
│  ○ Ollama        (local, no key needed)
│  ○ OpenAI        (paid)
│  ○ Anthropic     (paid)
│  ○ Gemini        (paid)
│
◆  Paste your API key
│  Get one free at console.groq.com
│  › ________________
│
└  ✔ Config saved to ~/.gcm/config.json

After setup it goes straight into generating your commit message.

Usage

git add .
gcm

The AI reads your staged diff, understands what changed and why, and generates a commit message. You then choose:

• Yes — commit with the message
• Edit — open in your editor to tweak first
• Regenerate — generate a new message
• Quit — exit without committing

Example Output

┌──────────────────────────────────────────────────────┐
│ refactor(auth): simplify token validation logic      │
│                                                      │
│ - replace manual JWT decode with jose library        │
│ - remove redundant session check in middleware       │
│ - fix edge case where expired tokens weren't caught  │
└──────────────────────────────────────────────────────┘

Commands

gcm                       # generate a commit message from staged changes
gcm init                  # re-run setup (switch provider or update API key)
gcm config                # view your current config
gcm config --reset        # delete config and start over
gcm --help (or -h)        # show help
gcm --version (or -v)     # show version

Supported Providers

| Provider | Free | API Key | |---|---|---| | Groq | ✅ Yes | Yes — console.groq.com | | Ollama | ✅ Local | No key needed | | OpenAI | ❌ Paid | Yes — platform.openai.com | | Anthropic | ❌ Paid | Yes — console.anthropic.com | | Gemini | ❌ Paid | Yes — aistudio.google.com |

Large Commits

If you stage too many files at once, gcm will warn you and suggest splitting:

⚠  Large diff detected — truncated for AI processing.
   Consider splitting this into smaller focused commits:
   1. Unstage everything    git restore --staged .
   2. Stage one concern     git add <specific files>
   3. Commit it             gcm
   4. Repeat for each concern

One commit should have one reason to exist. If you can't describe it in a single subject line without using "and" — split it.

Config

Config is saved at ~/.gcm/config.json and managed automatically. You never need to edit it manually.

To switch providers or update your API key at any time:

gcm init