Commit Message Generator

Purpose

Generate high-quality commit messages that:

• •Follow conventional commit format
• •Clearly describe changes
• •Provide useful context
• •Aid in changelog generation
• •Support semantic versioning

When to Use

Invoke this skill when:

• •User needs help writing commit messages
• •Reviewing staged changes for commit
• •Creating standardized team commit messages
• •Generating changelog entries
• •Teaching commit message best practices

Instructions

Step 1: Analyze the Changes

Examine the git diff to understand:

1. •Scope of change: What files/modules affected
2. •Type of change: Feature, fix, refactor, docs, etc.
3. •Impact: Breaking change or not
4. •Why: The reason for the change

Step 2: Determine Commit Type

Choose the appropriate conventional commit type:

• •feat: New feature
• •fix: Bug fix
• •docs: Documentation only
• •style: Formatting, missing semicolons, etc.
• •refactor: Code change that neither fixes a bug nor adds a feature
• •perf: Performance improvement
• •test: Adding or updating tests
• •build: Changes to build system or dependencies
• •ci: CI configuration changes
• •chore: Other changes that don't modify src or test files
• •revert: Reverting a previous commit

Step 3: Identify Scope (Optional)

Determine the scope (area of codebase):

• •Component name: auth, api, ui
• •Module name: parser, validator
• •Feature name: login, checkout

Step 4: Write the Subject Line

Create a subject line that:

• •Starts with type and optional scope: type(scope):
• •Uses imperative mood: "add" not "added" or "adds"
• •Is no longer than 50-72 characters
• •Does not end with a period
• •Clearly describes WHAT changed

Step 5: Add Body (if needed)

Include a body for complex changes:

• •Explain WHY the change was made
• •Describe the previous behavior
• •Explain the new behavior
• •Justify your approach
• •Wrap at 72 characters

Step 6: Add Footer (if needed)

Add footer for:

• •Breaking changes: BREAKING CHANGE: description
• •Issue references: Closes #123, Fixes #456
• •Co-authors: Co-authored-by: Name <email>

Examples

Simple Feature Addition

feat(auth): add password reset functionality

Implements password reset via email token. Users can now request
a password reset link that expires after 1 hour.

- Add /reset-password endpoint
- Implement email token generation
- Add reset form UI

Closes #142

Bug Fix

fix(api): resolve null pointer exception in user validation

The validator was not checking for null email values before
processing, causing crashes when users submitted empty forms.

Previous behavior: Crash on null email
New behavior: Return validation error message

Fixes #234

Breaking Change

feat(api)!: change authentication to JWT tokens

BREAKING CHANGE: Session-based auth is replaced with JWT tokens.
Clients must now include 'Authorization: Bearer <token>' header
instead of cookie-based sessions.

Migration guide:
1. Update API client to use Authorization header
2. Remove session cookie handling
3. Implement token refresh logic

Closes #567

Documentation Update

docs(readme): add installation instructions for Windows

Added step-by-step Windows installation guide including:
- Node.js version requirements
- Common PATH configuration issues
- WSL2 setup recommendations

Refactoring

refactor(parser): extract validation logic to separate module

Improves code organization and testability by moving validation
rules into dedicated validator module. No functional changes.

- Create validator.ts module
- Move validation rules from parser.ts
- Update tests to reflect new structure

Conventional Commit Format

<type>[(optional scope)][!]: <description>

[optional body]

[optional footer(s)]

Type + Scope Examples

feat(auth): ...
fix(api): ...
docs(readme): ...
style(button): ...
refactor(parser): ...
perf(query): ...
test(auth): ...
build(deps): ...
ci(github): ...
chore(release): ...

Subject Line Templates

Features

• •feat: add [feature]
• •feat(scope): implement [functionality]
• •feat: support [capability]
• •feat: enable [feature]

Fixes

• •fix: resolve [issue]
• •fix(scope): correct [problem]
• •fix: prevent [error]
• •fix: handle [edge case]

Refactoring

• •refactor: extract [component]
• •refactor: simplify [logic]
• •refactor: reorganize [structure]
• •refactor: rename [element] to [new name]

Documentation

• •docs: add [documentation]
• •docs: update [section]
• •docs: improve [content]
• •docs: fix typo in [location]

Best Practices

Subject Line

1. •Imperative mood: "add" not "added" or "adds"
2. •No period: at the end
3. •Length: 50 characters ideal, 72 max
4. •Capitalize: First letter after type
5. •Specific: What changed, not how

Body

1. •Wrap: at 72 characters
2. •Explain WHY: not what (what is in the diff)
3. •Context: Provide background
4. •Bullet points: OK for listing changes
5. •Blank line: Between subject and body

General

1. •Atomic commits: One logical change per commit
2. •Test: Ensure tests pass before committing
3. •Review: Read the diff before writing message
4. •Consistent: Follow team conventions
5. •Meaningful: Help future developers (including you)

Common Mistakes to Avoid

1. •Vague messages: ❌ "fix stuff" → ✅ "fix: resolve login timeout issue"
2. •Past tense: ❌ "added feature" → ✅ "add feature"
3. •Too long: ❌ 100+ character subject lines
4. •Too generic: ❌ "update code" → ✅ "refactor(auth): extract validation logic"
5. •No context: ❌ "fix bug" → ✅ "fix(api): handle null values in user input"

Scope Suggestions by Project Type

Frontend

• •ui, component, layout, style, form, nav, header, footer

Backend

• •api, auth, db, model, controller, middleware, service

Full Stack

• •client, server, shared, config, types, utils

DevOps

• •ci, cd, docker, k8s, deploy, monitoring, logging

Templates for Complex Scenarios

Multiple Related Changes

feat(api): add user profile management endpoints

Implements CRUD operations for user profiles including:
- GET /users/:id/profile - Fetch profile
- PUT /users/:id/profile - Update profile
- POST /users/:id/profile/avatar - Upload avatar
- DELETE /users/:id/profile/avatar - Remove avatar

All endpoints include proper authentication and authorization.

Closes #123, #124, #125

Dependency Update

build(deps): upgrade React from 17.0.2 to 18.2.0

Major version update with breaking changes in:
- Concurrent rendering API
- Automatic batching behavior
- SSR changes

Updated all components to use new createRoot API.
All tests passing with new version.

BREAKING CHANGE: Requires Node.js >= 14.0.0

Emergency Hotfix

fix(security): patch XSS vulnerability in comment rendering

SECURITY: User-submitted comments were not properly sanitized,
allowing script injection attacks.

Solution: Implement DOMPurify sanitization on all user content
before rendering.

Severity: High
Affected versions: 1.0.0 - 1.2.3
Fixed in: 1.2.4

CVE-XXXX-XXXXX

Output Format

<type>(<scope>): <subject>

<body paragraph 1>

<body paragraph 2>

<footer>

Related Skills

• •git-workflow-guide: For overall git workflows
• •changelog-generator: For creating changelogs from commits
• •pr-description-generator: For pull request descriptions
• •semantic-versioning: For version bumping based on commits