draft-commit

name	draft-commit
description	Analyze staged git changes and draft a commit with a structured message following project conventions
disable-model-invocation	true
allowed-tools	Bash(git *)

Context

Analyze the staged git changes or those of a commit if specified by the use. Draft a commit message following the project's conventions, and draft the commit message.

Step 1: Gather context

Run these commands in parallel:

• git status to see staged and unstaged files (never use -uall)
• git diff --cached to see the staged diff
• git diff --cached --stat for a file summary
• git log --oneline -10 for recent commit style reference

If nothing is staged, tell the user and stop. Do not stage files automatically — ask the user which files to stage if there are unstaged changes.

Step 2: Determine the module tag

Infer the tag from the changed file paths using this mapping:

Path prefix	Tag
efb/src/route/	route
efb/src/fp/	fp
efb/src/measurements/	measurements
efb/src/nd/	nd
efb/src/fms/	fms
efb/src/core/	core
efb/src/aircraft/	aircraft
efb/src/geom/	geom
efb/src/fc/	fc
arinc424/	arinc424
aixm/	aixm
handbook/	handbook
bindings/c/	c
bindings/wasm/	wasm
bindings/python/	python
bindings/swift/	swift

Rules:

• If all meaningful changes fall within one module, use that tag.
• If binding changes merely mirror a core module change (e.g. updating a C binding wrapper because the Rust API changed), use the core module's tag.
• If changes span multiple unrelated modules, omit the tag entirely.
• Files like CLAUDE.md, CONTRIBUTING.md, .github/, Cargo.toml are not module-specific — ignore them when determining the tag unless they are the only changes (then omit the tag).

Step 3: Draft the commit message

Follow these formatting rules:

Title line

• Format: tag: Imperative summary (or just Imperative summary if no tag)
• Maximum 50 characters including the tag and colon
• Use imperative mood: Add, Fix, Remove, Refactor, Implement, Wire, Compute, Extract
• Never use vague words: "update", "change", "stuff", "misc", "various"
• Capitalize the first word after the tag

Body (optional, use when the diff is non-trivial)

• Separate from the title with one blank line
• Wrap lines at 72 characters
• Explain the why, not the what — the diff shows the what
• Use bullet points for multiple distinct changes
• If there is a breaking change, add BREAKING CHANGE: followed by a description

Step 4: Create the commit message

• Simply print the commit message but let the user do the commit:

tag: Title here

Body here.