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name: commit-message description: Format git commit messages combining Conventional Commits summary lines with Linux kernel-style bodies. Use when writing, reviewing, or formatting commit messages.

Commit Message Formatting

Summary Line

Use Conventional Commits format:

Copy<type>(<scope>): <description>

• type (required): feat, fix, docs, style, refactor, perf, test, build, ci, chore
• scope (optional): component or area affected, in parentheses
• description: imperative mood, lowercase start, no period, max 50 chars (hard limit 72)
• For breaking changes: add ! before colon: feat(api)!: remove deprecated endpoint

Body

Separate from summary with blank line. Follow kernel style:

• Wrap at 72 columns
• Imperative mood ("Add feature" not "Added feature")
• Explain why, not what (the diff shows what)
• Describe user-visible impact and motivation
• Quantify improvements with numbers when applicable

When referencing commits, use 12+ char SHA with summary:

CopyCommit e21d2170f36602ae2708 ("video: remove unnecessary
platform_set_drvdata()") introduced a regression...

No Trailers

Omit all trailers: no Signed-off-by, Reviewed-by, Acked-by, Tested-by, Cc, Fixes, Link, etc.

Examples

Single-line fix:

Copyfix(parser): handle empty input without panic

Feature with body:

Copyfeat(auth): add OAuth2 PKCE flow support

Mobile and SPA clients cannot securely store client secrets. PKCE
allows these clients to authenticate safely without exposing
credentials in client-side code.

This reduces authentication failures for mobile users by eliminating
the insecure implicit flow workaround.

Breaking change:

Copyfeat(api)!: require authentication for all endpoints

Anonymous access created security vulnerabilities and complicated
rate limiting. Requiring auth simplifies the security model and
enables per-user quotas.

Clients must now include a valid Bearer token with every request.

Refactor:

Copyrefactor(db): extract connection pooling into dedicated module

The monolithic database module grew to 2000+ lines, making
maintenance difficult. Separating connection pooling improves
testability and allows independent configuration tuning.