generate-git-commit

name	generate-git-commit
description	Generates git commit messages from current diff or PR messages from last N commits using the embedded TF4 GitHub branch/commit/PR convention. Use when the user asks to auto-generate a commit message, git commit message, PR message, pull request body, release PR summary, or asks for "auto git commit".

Skill: generate-git-commit

Generate a commit message or PR message from real git changes, using the embedded convention below. Do not invent another convention.

Never commit, push, stage, open a PR, rewrite history, or otherwise mutate repo state unless the user explicitly asks after seeing the generated message.

Convention

Commit message format

<type>[optional scope]: <description>

[optional body]

Allowed types:

Type	Meaning
fix	bug fix
feat	new/updated feature
build	build system, Docker, dependency, package manager
chore	supporting work, no app behavior change
docs	documentation
style	formatting/whitespace/lint, no logic change
refactor	refactor, no new feature, no direct bug fix
perf	performance improvement
test	add/update tests

Description: short, imperative mood if English, no trailing period. Body only when it explains "why".

Suggested scopes: frontend, checkout, cart, payment, product-catalog, product-reviews, llm, kafka, db, helm, deploy, observability, ci, docs

Example: fix(payment): add readiness probe before receiving traffic

If the diff is mixed (multiple unrelated concerns), recommend splitting into 2-4 separate commits instead of one.

PR convention

Title uses the same format: <type>(<scope>): <description> — repo squashes/rebases, so this title often becomes the final commit message. Make it precise.

Required PR body template:

## Summary
- 

## Why
- 

## Changes
- 

## Verification
- [ ] test/lint/build pass
- [ ] helm template pass if touching chart/deploy
- [ ] deploy/smoke test if touching runtime

## Risk & rollback
- Risk:
- Rollback:

## Scope
- Team: AIO01 / CDO04 / CDO07 / CDO08
- Area:

PR size: one clear goal per PR, ideally <300-500 line diff; keep docs-only separate from code/config changes; keep refactors separate from behavior changes.

Pipeline

[0. Ask Mode] → [1. Fan-out Git Exploration] → [2. Synthesize] → [3. Convention Check]

Stage 0 — Ask Mode

Ask the user to pick a mode before inspecting anything. Do not guess:

Choose mode:
1. Generate commit message from current git diff
2. Generate PR message from the last N commits

If 2, tell me N.

Stage 1 — Fan-out Git Exploration

Spawn one read-only subagent (Explore type, or general-purpose with strict read-only instructions). It must not edit, stage, commit, push, create a PR, delete a branch, or rewrite history.

Mode 1 — current diff. Report: whether a staged diff exists (use staged diff only if so, else unstaged working tree diff; if no diff at all, say so — don't fabricate a message); files grouped by scope; user-facing/config/docs/test changes; likely type + scope; whether the diff is mixed and should be split; breaking change (yes/no + evidence); verification hints.

Useful commands: git status --short, git diff --cached --stat, git diff --cached, git diff --stat, git diff

Mode 2 — last N commits / PR message. Ask for N if missing. Report: commit list (hashes + subjects); aggregate diff summary; files grouped by scope; feature/fix/docs/config/test/runtime impact; likely PR title; PR body content for each required section; breaking change (yes/no + evidence); verification hints. If HEAD~N doesn't exist, use what's available and state the limitation.

Useful commands: git log --oneline -n <N>, git diff --stat HEAD~<N>..HEAD, git diff HEAD~<N>..HEAD

Stage 2 — Synthesize

Use only the embedded convention and the subagent's evidence — no unsupported claims.

Commit message output:

Recommended commit message:

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

[optional body]

Why:
- type: ...
- scope: ...
- evidence: ...

Optional alternatives:
- ...

PR message output:

Recommended PR title:

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

Recommended PR body:
[filled template from above]

Why:
- title type/scope: ...
- main areas: ...
- risk: ...

Stage 3 — Convention Check

Before answering, verify: type is one of the 9 allowed; scope is from the list or intentionally omitted; no trailing period; PR body uses the exact template sections; text reflects real diff/commit evidence; no mutating command was run.

Hard safety boundaries

Never run these unless the user explicitly asks after seeing the generated message, and only after they confirm the exact message:

git add · git commit · git push · gh pr create
git branch -d/-D · git reset · git rebase · git tag · git merge

Response style

Message first, explanation short. For a mixed diff:

Diff mixed. Better split:
1. docs(...): ...
2. fix(...): ...

No essays, no git lecture.