# Commit Msg > Write a Conventional Commit message from a description of changes. Lead with WHY, not WHAT. - Skill: `kewang0622/commit-msg` (Agent Skill) - Install (CLI): `npx skillmds@latest add kewang0622/commit-msg` - Raw SKILL.md: https://api.skillmd.com/api/skills/kewang0622/commit-msg/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: kewang0622 (https://skillmd.com/u/kewang0622) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/kewang0622/commit-msg --- # Commit Message Writer When the user asks for a commit message, write a Conventional Commit. ## Format ``` (): ``` `` is one of: `feat`, `fix`, `refactor`, `perf`, `docs`, `test`, `chore`, `build`, `ci`, `style`, `revert`. ## Subject line rules - ≤ 70 characters. - Imperative mood (`add`, `fix`, `rename` — not `added`, `fixes`, `renaming`). - No trailing period. - Lowercase first word after the colon. - Lead with the WHY when it's non-obvious. *"fix(auth): clear session on tab close to prevent stale tokens"* beats *"fix(auth): update logout handler"*. ## When to add a body Add a body only if the subject can't carry the whole story. The body explains: - *why* (the user-visible problem this solves) - *what changed* in shape (not a line-by-line diff — that's what `git diff` is for) - *anything subtle* a future reader needs to understand the change Wrap body lines at 72 chars. One blank line between subject and body. ## Anti-patterns - ❌ `update code` — say what and why - ❌ `fix bug` — say which bug - ❌ `WIP` — squash before committing - ❌ `refactor: cleanup` — describe the cleanup ## When the user only describes the change Ask zero questions. Make a confident first attempt and offer to revise. Most users would rather edit your guess than answer your interview.