# Commit Message

> Write clear conventional commit messages from git diffs or change descriptions. Use when committing, writing commit messages, or summarizing staged changes. Do NOT use for PR descriptions or release notes.

- Skill: `bjg4/commit-message-4` (Agent Skill)
- Install (CLI): `npx skillmds@latest add bjg4/commit-message-4`
- Raw SKILL.md: https://api.skillmd.com/api/skills/bjg4/commit-message-4/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: bjg4 (https://skillmd.com/u/bjg4)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/bjg4/commit-message-4

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# Commit Message

## Quick start

From the diff or change summary, produce:
- Subject: imperative, ≤72 chars, conventional type if clear (`feat:`, `fix:`, `docs:`)
- Body (optional): what and why, wrapped at 72 chars

## Conventional commits

| Type | When |
|------|------|
| feat | New capability |
| fix | Bug fix |
| docs | Documentation only |
| refactor | Behavior-preserving restructure |

Default to `feat` or `fix` when obvious; otherwise omit prefix and write a clear subject.

## Error handling

If no diff or summary provided, ask for `git diff --staged` output or a one-line change description.