commit-msg

Commit Message Generator

Generate a one-line commit message from the changes on the current branch.

Announce at start: "Generating commit message..."

Process

Step 1: Gather Changes

Run:

git diff HEAD~1..HEAD --stat
git diff HEAD~1..HEAD

If there are uncommitted changes (staged or unstaged), use this instead:

git diff HEAD --stat
git diff HEAD

To decide which, first check:

git status --porcelain

If there is output (uncommitted changes exist), diff against HEAD. Otherwise diff against HEAD~1.

Step 2: Incorporate Conversation Context

Before generating the message, check for context from the current conversation that can inform the why behind the changes:

• Implementation plan: If there is an active plan (from superpowers:writing-plans, superpowers:executing-plans, or similar), note the goal, motivation, and relevant plan step being completed.
• Conversation history: If the current session includes discussion about what problem is being solved, what feature is being added, or what bug is being fixed, use that intent to write a more accurate message.
• Task context: If tasks were created during the session, reference the task descriptions for additional context on purpose.

Use this context to capture the why — the diff alone often only shows the what.

Step 3: Generate the Message

Write a single-line commit message:

• Imperative mood ("Add", "Fix", "Update", not "Added", "Fixes", "Updates")
• Under 72 characters
• No period at the end
• Focus on what and why, not how
• Conventional style (e.g., "Add user authentication endpoint", "Fix null check in payment handler")
• If conversation/plan context provides a clearer why than the diff alone, prefer that framing

Step 4: Output

Print the message as a code block so it's easy to copy:

<the commit message>

Do not run any git commands that modify the repository. This skill is read-only.