| name | commit-message |
| description | Generates a structured Git commit message (header + Motivation / Overview / Main Changes / Breaking Changes sections) from staged diffs. Use when the user asks to write or generate a commit message. |
| argument-hint | Optionally paste extra context. The skill runs git diff automatically. |
Structured Commit Message Generator
Procedure
- Run both commands to collect inputs:
git --no-pager diff --cached --stat
git --no-pager diff --cached --minimal
- From the diff, classify each changed file as add / change / remove / move.
- Detect breaking changes (see hints below). If any exist, append
! to the header prefix.
- Output one commit message using the Style Reference below. Request missing inputs only when necessary.
Style Reference
feat: summary of diff changes
**Motivation**
why this change is needed.
**Overview**
- key point 1 of the change
- key point 2 of the change
**Main Changes**
- file/path/one.rb (add/change/remove/move): brief explanation of change
**Breaking Changes (Important)**
- description of breaking change 1
Omit **Breaking Changes** when there are none.
Output Requirements
- Header: Conventional Commits prefix (
feat:, fix:, refactor:, chore:, etc.), ! when breaking, ≤72 chars.
- Include a scope only when clearly implied by the diff.
- Sections in order: Motivation → Overview → Main Changes → (Breaking Changes).
- "Main Changes" must label each file with add / change / remove / move explicitly.
Breaking Change Hints
Flag as breaking when the diff shows:
- Public interface changes (method signatures, API endpoints, return types)
- Config key additions or renames (default values, env vars)
- DB migrations adding tables or required columns
- Test expectations updated to match changed behaviour
- Operational requirements introduced (HTTPS, new env var required)
