Git Atomic Commit

Git Atomic Commit

Overview

This skill enables crafting clean, atomic git commits with conventional commit messages by analyzing all changes in the repository, intelligently grouping them into logical commits, and guiding the user through the process.

⚠️ Critical: Distinguish Commit Type vs. Commit Scope

Commit messages follow the pattern type(scope): subject. Type and Scope are governed by a three-tier hierarchy:

Commit Types = Tier 1 + Tier 2. Types represent the intent of the change. Commit Scopes = Tier 3. Scopes represent the domain, module, or location of the change, tightly coupled to the repository's context.

Tier 1: Universal Commit Types

Standard Conventional Commits — these are immutable and apply everywhere:

Tier 2: Author Preferences (Opinionated Extended Types)

Note for other users: These extended types reflect the author's (arisng) personal conventions for AI/DevTool-heavy repositories. You are free to modify, remove, or add your own extended types to suit your workflow.

Extended types take precedence over universal types when the file matches a known pattern:

Rule: When a file matches an extended type pattern, always use the extended type instead of the universal one. Fall back to universal types for everything else.

Tier 3: Workspace-Specific (Scopes + Overrides)

Scopes are entirely repo-specific and governed by .github/git-scope-constitution.md. The file-path-to-scope mapping below is an example from the author's workspace. Each repository should define its own via the git-commit-scope-constitution skill.

Scope Granularity Principle: Scopes represent the artifact category, not a specific instance. When scanning git log --oneline, type(category) tells you what kind of thing changed; the commit subject tells you which one.

File Assignment Rules

MANDATORY STEP: Before any grouping or planning, assign a Commit Type and a Commit Scope to EACH changed file individually. Files with different types or unrelated scopes MUST be in separate commits — this is non-negotiable for atomicity.

Critical Rules:

• Different commit types = Different commits — Even related files must be separated if they have different types.
• Different scopes = Usually different commits — Keep commits atomic by scope unless the change is a cross-cutting concern.
• Extended type wins — If a file matches a Tier 2 pattern, never use a Tier 1 universal type.
• Check mapping first — Assign types and scopes to individual files before considering relationships.

Common Mistakes to Avoid:

• ❌ Conflating type and scope: docs(issue) is NOT a type. docs is the type, issue is the scope.
• ❌ feat(instructions) → ✅ copilot(instruction) — Use extended type copilot (Tier 2)
• ❌ feat(skill) → ✅ agent(skill) — Use extended type agent (Tier 2)
• ❌ ai(skill) → ✅ agent(skill) — ai type is deprecated; use agent for all AI model-facing behavior
• ❌ ai(agent) → ✅ agent(instruction) — deprecated ai type; the old agent scope maps to instruction under agent
• ❌ chore(issue) → ✅ docs(issue) — docs is the appropriate universal type
• ❌ docs (no scope) → ✅ docs(issue) or docs(changelog) — Always include a scope
• ❌ agent(pdf) → ✅ agent(skill) — Use category-level scope, put specific item in subject
• ❌ Mixing copilot(mcp) + devtool(vscode) in one commit → ✅ Separate commits
• ❌ Grouping files with different types → ✅ One type per commit

Workflow

1. Analyze All Changes

• Retrieve all changed files (both staged and unstaged)
• If no changes exist, inform the user there's nothing to commit
• Read relevant file diffs to understand the nature of each change

2. Assign Commit Types and Scopes to Individual Files

MANDATORY: For each changed file, determine its exact commit type AND scope using the mapping table above. Document this assignment - it drives the entire commit strategy.

3. Validate Scope Selection

MANDATORY: After types and scopes are assigned, validate scope choices.

Scope Validation Process:

1. Check if repository has a scope constitution at .github/git-scope-constitution.md
2. If constitution exists, verify chosen scopes are approved for their commit type
3. If no constitution exists, use the git-commit-scope-constitution skill to:
   • Analyze repository structure (folders, modules, domains)
   • Extract historical scopes from git history
   • Propose appropriate scopes based on project structure
4. Ensure scope names follow conventions:
   • Kebab-case, lowercase, singular form
   • Domain/module/feature-based (not file-path-based)
   • Concise and descriptive (1-3 words)

Scope Cross-Reference:

• Commit type (Tier 1/2) determines WHAT kind of change
• Scope (Tier 3) specifies WHERE in the project
• Together they form: type(scope): subject

Example:

File: skills/pdf/SKILL.md
  → Type: agent            [Tier 2 extended type for AI agent assets]
  → Scope: skill           [Tier 3 category-level scope]
  → Result: agent(skill): add table extraction to pdf

4. Pre-Commit Verification Checklist

MANDATORY: Complete this checklist before presenting any commit plan:

• Type Mapping: Every file path mapped to correct type (Tier 2 extended type when applicable, otherwise Tier 1 universal)
• Scope Selection: Every commit has an appropriate scope from the constitution (Tier 3)
• No Generic Types: No commits using Tier 1 types (feat, fix, chore) when a Tier 2 extended type applies
• Atomic Grouping: Changes grouped by logical feature/module boundaries
• Dependency Order: Commit order maintains buildable state
• Scope Accuracy: Commit scopes match actual module/feature names

If any checklist item fails, revise the plan before proceeding.

5. Group Changes into Logical Commits

CRITICAL CONSTRAINT: Files with different commit types CANNOT be grouped together - they must be in separate commits.

Group remaining related changes based on:

• Same commit type: Only group files that share the same required commit type
• Feature scope: Files related to the same feature/module (within same type)
• Change type: Separate refactors from features from fixes (within same type)
• Domain boundaries: Respect module/bounded context boundaries (within same type)
• Dependencies: Ensure commits can be applied sequentially without breaking the build

If grouping would mix commit types, split into separate commits immediately.

Create a todo list tracking each planned commit with their assigned types.

6. Validate Commit Plan

MANDATORY VALIDATION: Review each planned commit to ensure:

• All files in a commit share the same commit type
• No commit mixes different types
• Each commit represents one logical change within its type
• Commits can be applied in sequence without conflicts
• Scopes are valid per the constitution (if available)

If validation fails, revise the grouping immediately.

7. Generate Conventional Commit Messages

For each group, generate a commit message following Conventional Commits format:

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

<body>

<footer>

MANDATORY: Conventional Commit Syntax Every commit MUST follow this exact structure:

• <type>(<scope>): <subject>
• Never use multiple scopes like <type>(<scope>)(<scope_2>) or <type>(<scope1,scope2>). Use ONE primary scope that best represents the change.
• Secondary Areas: If the change involves a second area (scope_2), mention it explicitly inside the <subject> part (e.g., <type>(primary-scope): [scope2] actual message or <type>(primary-scope): fix scope2 bug).

Message Format Rules:

• Type: Must be a Tier 1 universal type or Tier 2 extended type (see tables above).
• Scope: Must be a single, concise module or feature name (Tier 3).
• Subject: Imperative mood, lowercase, no period, ≤50 chars
• Body: Explain what and why, wrap at 72 chars

Type Selection: Refer to the Tier 1 and Tier 2 tables in the "Distinguish Commit Type vs. Commit Scope" section above.

CRITICAL: Use Tier 2 extended types (e.g., agent, copilot) instead of Tier 1 universal types (feat, chore) when the file matches an extended type pattern. Always pair the Type with a valid Scope from the repository's constitution.

Scope Selection:

• Prefer scopes from .github/git-scope-constitution.md if available
• Ensure scope aligns with repository structure (module, domain, feature)
• Follow kebab-case, lowercase naming conventions
• Use git-commit-scope-constitution skill if unclear

8. Commit Message Quality Standards

KEY: Provide sufficient detail for accurate changelog generation and knowledge graph tracking. Vague messages lead to misleading summaries.

Quality Requirements:

• Deletions: List specific items removed (files, features, agents, etc.)
• Bulk changes: Specify each major component affected
• Refactors: Detail what was restructured and why
• Additions: Describe new capabilities or features clearly

Good Example (Specific):

copilot(custom-agent): remove unused agents - conductor, context7, implementation, microsoft-docs

Removes four specialized agents that were redundant.
Streamlines agent portfolio and reduces maintenance overhead.

Bad Example (Vague):

refactor: update agent definitions

9. Execution & Review

Interactive Mode (User-Guided):

1. Present the complete commit plan with all details.
2. Wait for explicit user approval before proceeding.
3. Execute commits sequentially:
   • Stage only files for the current commit
   • Execute commit
   • Confirm success
4. Allow user to edit or reject commits.

Autonomous Mode (Subagent):

1. Analyze changes and generate the complete commit plan.
2. Validate internally against all constraints.
3. Execute all planned commits automatically without user prompts.
4. Return a comprehensive summary of all created commits.

Safety:

• Never discard or reset changes without consent.
• If validation fails, stop and report the issue.

10. Completion

After all commits are done, show a summary of all commits created.

Constraints

• Never commit without explicit user approval (unless operating in authorized autonomous mode)
• Never discard or reset user's changes
• MANDATORY: Use project-specific commit types - no exceptions
• MANDATORY: Complete pre-commit verification checklist
• MANDATORY: Different commit types require separate commits - No exceptions for atomicity
• MANDATORY: Use approved scopes from constitution - Check .github/git-scope-constitution.md if available
• Keep commits atomic: one logical change per commit
• Ensure commit order maintains a buildable state
• Use English for all commit messages unless instructed otherwise

Integration with git-commit-scope-constitution Skill

This skill works in tandem with the git-commit-scope-constitution skill to ensure complete commit message consistency:

Division of Responsibility:

• git-atomic-commit (this skill):

  • Maps file paths to commit types
  • Groups changes into atomic commits
  • Validates commit structure and ordering
  • Executes commits with user approval

• git-commit-scope-constitution:

  • Defines valid scopes for each commit type
  • Maintains scope naming conventions
  • Aligns scopes with repository structure
  • Provides scope selection guidelines

Workflow Integration:

Changed Files
    ↓
git-atomic-commit: Map files → Commit types
    ↓
git-commit-scope-constitution: Select scopes for each type
    ↓
git-atomic-commit: Generate commit messages
    ↓
Final Commits: type(scope): subject

When to Use Each:

• Use git-atomic-commit for every commit workflow
• Use git-commit-scope-constitution when:
  • Repository lacks .github/git-scope-constitution.md
  • Need to add new scopes
  • Weekly constitution refinement
  • Scope selection is unclear

Constitution Location: .github/git-scope-constitution.md Scopes Inventory: .github/git-scope-inventory.md

Commands Reference

# View all changed files (staged + unstaged)
git status --short

# View diff for unstaged changes
git diff -- <filepath>

# View diff for staged changes
git diff --cached -- <filepath>

# Stage specific files
git add <filepath>

# Unstage specific files
git reset HEAD -- <filepath>

# Commit with message
git commit -m "<message>"

# Commit with multi-line message
git commit -m "<subject>" -m "<body>"

Example Output

📦 Commit Plan (3 commits)

1. agent(skill): add vscode-docs skill for researching VS Code docs
   Files: skills/vscode-docs/SKILL.md, skills/vscode-docs/assets/toc.md

2. copilot(instruction): update claude-skills orchestration guidelines
   Files: instructions/claude-skills.instructions.md

3. docs(issue): remove deprecated copilot-skills design decision issue
   Files: .issues/251210_copilot-skills.md

✅ Pre-commit verification: All file paths mapped to correct project-specific types
Ready to proceed with commit #1? (yes/no/edit)

Error Handling

• If a commit fails, show the error and ask how to proceed
• If conflicts arise, guide the user to resolve them
• Always provide a way to abort and restore original staging state
• If commit types are incorrect, stop and revise the entire plan
• If validation fails due to type mixing, immediately revise the grouping