Commit Skill

Write clean, consistent git commit messages that are easy to scan and understand.

Commit Message Format

Subject line in sentence case

Optional body that explains why the change was made, wrapped at 72
characters per line. The body should focus on *why* not *what* (the diff
shows what changed).

Author: Agent via <model>

Subject Line Rules

• Sentence case: Capitalize only the first word (not a title)
• Imperative mood: Start with a verb like Add, Fix, Refactor, Update, Remove
• Concise: ~50-72 chars max — summarize the change, not the file
• No period: Subject lines don't end with punctuation
• No prefixes: No feat:, fix:, or conventional commits notation

Good Examples

Add dark mode toggle to settings page
Fix race condition in WebSocket reconnect logic
Refactor pricing calculator into composable hooks
Remove unused analytics middleware
Update password validation to enforce minimum entropy
Collapse sidebar navigation on mobile viewports

Bad Examples

feat: Add new feature          ❌ No conventional commits prefix
Fixed Bug                      ❌ Not imperative mood, capitalized wrong
update code                    ❌ Not capitalized, too vague
Add new feature.               ❌ No trailing period
Updated: user-profile.tsx      ❌ File name as subject
FIX AUTHENTICATION             ❌ No all caps

When to Use a Body

Include a body when:

• Multi-file changes need context
• The why isn't obvious from the diff
• There are breaking changes or behavioral shifts
• You need to reference issues, links, or related work

Anti-Patterns

• ❌ Vague messages: "Update code", "Fix bug", "Changes"
• ❌ File lists as the subject
• ❌ Conventional commits prefixes (feat:, fix:, chore:)
• ❌ ALL CAPS or Title Case Everywhere
• ❌ Trailing periods on subject line
• ❌ Subject longer than 72 characters

Git Commands

# Simple commit
git add -A
git commit -m "Add user profile page" -m "Author: Agent via Opus 4.6"

# Commit with body
git add -A
git commit -m "Fix authentication flow" \
  -m "Previous implementation didn't handle expired tokens correctly. Now we refresh tokens before making API calls if they're within 5 minutes of expiry." \
  -m "Author: Agent via Opus 4.6"

Attribution

Always include your model in the last line of the commit description:

Author: Agent via Opus 4.6
Author: Agent via Sonnet 4.5
Author: Agent via DeepSeek R1

This helps track which models produced which work and improves accountability.