git-aicommit

A tiny Rust CLI that drafts a commit message from your staged changes using OpenAI Codex or Claude Code, then opens git commit with the message pre-filled so you can review, edit, or abort.

Install

# Homebrew (macOS/Linux)
brew install getkono/tap/git-aicommit

# crates.io (requires Rust)
cargo install git-aicommit

# Pre-built binary — download from the latest release, then:
#   https://github.com/getkono/git-aicommit/releases/latest
tar xzf git-aicommit-x86_64-unknown-linux-musl.tar.gz
mv git-aicommit ~/.local/bin/

# From source (requires Rust)
cargo build --release
cp target/release/git-aicommit ~/.local/bin/

The binary must be named git-aicommit and be on your $PATH for git to pick it up as the git aicommit subcommand.

Requirements

• git
• At least one agent CLI, installed and authenticated: codex 0.146.0+ or claude 2.x

Usage

git add -p
git aicommit

Your editor opens with the drafted message. Save to commit, or quit with an empty message to abort.

git aicommit -a                          # include all tracked changes
git aicommit --amend                     # redraft from previous message + diff
git aicommit -m "call out the perf fix"  # steering instruction, NOT a literal message
git aicommit -y --push                   # skip the editor, push after committing
git aicommit --dry-run                   # print the message and exit

git aicommit is a drop-in for git commit: unrecognized flags are forwarded verbatim, and git aicommit --help lists everything it handles itself.

Choosing the agent and model

Codex runs when codex is on your $PATH, otherwise Claude. Pass --agent codex|claude to pin one.

The model is picked from the size of the change — gpt-5.6-luna → gpt-5.6-terra for Codex, haiku → sonnet for Claude — escalating once a diff exceeds 16KB or touches 8 files, since that's where a single-pass summary starts dropping detail. Pass --model <name> to pin one.

--agent and --model must come before any git flags. There is no API key handling here; auth is delegated entirely to the local codex or claude CLI.

Notes

• The prompt asks for Conventional Commits style (feat:, fix:, …), an imperative subject ≤72 chars, and an optional body explaining the why. When a commit bundles unrelated changes, the subject leads with the primary one and the body itemizes the rest.
• For plain and --amend commits, the pre-commit hook runs before any API call, so a failing hook costs you nothing. -n/--no-verify skips both that pre-check and the hook at commit time.

Using it from your own application

The message-generation logic lives in a separate library crate, aicommit-core, so other frontends can reuse it. Hand it a diff and it hands you a string; it never invokes git. See its README and examples/editor.rs.