mm - Rust CLI

mm is a Rust rewrite of the MichaelCurrin/auto-commit-msg logic with:

• Copying AI Agent chat logs with only one command.
• "commitlint" rules.
• No AI, save tokens.

It generates a Conventional Commit message from Git changes and commits in one step:

mm

By default there is no AI or network call. The message is built from the paths and change types that Git reports. If the project has a commitlint configuration, its type, scope and length rules are applied too. Inside OpenCode, Antigravity, Claude Code, Codex, Devin / Codeium, or Freebuff / Codebuff, --chat, --opencode, --agy, --claude, --codex, --devin, or --freebuff can copy the session/prompt and last assistant message instead; see Using an OpenCode, Antigravity, Claude Code, Codex, Devin / Codeium, or Freebuff / Codebuff chat.

Problems

• Ask AI Agents, LLMs to commit changes is waste of tokens.
• Commit messages already is logs from AI Agent.
• Simple create, update, delete a file not worth for AI Agent.

Install

Homebrew (macOS & Linux)

brew tap loclv/tap
brew install mm

cargo-binstall (Pre-built Binaries)

Install pre-compiled binaries fast without building from source:

cargo binstall mm

Pre-compiled Binaries (GitHub Releases)

Download pre-built archives for Linux (x86_64, aarch64), macOS (Intel, Apple Silicon), and Windows from GitHub Releases.

From Source

cargo install --path .

To build without installing:

cargo build --release
./target/release/mm --help

Usage

mm # Generate a message and commit
mm --print # Show the message without committing
mm --add # Stage everything (including new files), then commit
mm --edit # Open the editor before committing
mm --staged # Use only staged changes
mm --chat # Copy the current OpenCode, Antigravity, Claude Code, Codex, Devin, or Freebuff chat
mm -o # Copy the current OpenCode session (same as --opencode)
mm --agy # Copy the latest Antigravity log commit message
mm --claude # Copy the latest Claude Code log commit message
mm --codex # Copy the latest Codex log commit message
mm --devin # Copy the latest Devin / Cascade log commit message
mm --freebuff # Copy the latest Freebuff / Codebuff log commit message
mm -m 'JIRA-1: fix' # Keep an existing prefix/description (or override a chat subject)
mm --completions zsh # Print shell completions (bash, zsh, or fish)

Run mm --help for the full option list. See docs/usage.md for macOS/zsh installation, the complete command reference, and troubleshooting.

Message format

Generated headers follow the Conventional Commits specification by default, for example feat: create foo.rs or chore: update 5 files. When no type can be inferred, mm uses chore.

To disable the convention, add mm.json in the project (the file is searched for from the current directory upwards, stopping at your home directory):

{
  "conventionalCommits": false
}

Messages then use plain descriptions such as update README.md. An explicit --message prefix is still preserved, and commitlint rules still apply.

By default, mm automatically stages all changes (including untracked files) when running without any staged changes. To disable this, set "autoAdd": false in mm.json:

{
  "autoAdd": false
}

Using an OpenCode, Antigravity, Claude Code, Codex, Devin / Codeium, or Freebuff / Codebuff chat

mm can extract the commit message from OpenCode, Antigravity, Claude Code, Codex, Devin / Codeium, or Freebuff / Codebuff chats:

mm --chat --print # preview the message (auto-detects OpenCode, Antigravity, Claude Code, Codex, Devin, or Freebuff)
mm --opencode --print # preview message from the current OpenCode session
mm --agy --print # preview message from the latest Antigravity log
mm --claude --print # preview message from the latest Claude Code log
mm --codex --print # preview message from the latest Codex log
mm --devin --print # preview message from the latest Devin / Cascade log
mm --freebuff --print # preview message from the latest Freebuff / Codebuff log
mm --freebuff # commit using the latest Freebuff / Codebuff log

• OpenCode: OPENCODE_SESSION_ID selects the session; --opencode / -o forces OpenCode. The subject is the session title (or latest user prompt line), and the body is the last assistant message (or compaction summary).
• Antigravity: Transcript logs from ~/.gemini/antigravity-ide/brain (or ANTIGRAVITY_CONVERSATION_ID) are read. The subject is the latest user request line, and the body is the last assistant response.
• Claude Code: Transcript logs from ~/.claude/projects/ (or CLAUDE_SESSION_ID) are read. The subject is the latest user prompt line, and the body is the last assistant text response.
• Codex: Transcript logs from ~/.codex/sessions/ (or CODEX_SESSION_ID) are read. The subject is the thread title from session_index.jsonl (or latest user prompt line), and the body is the last assistant response.
• Devin / Codeium: Devin ATIF JSON/JSONL transcripts and Codeium Windsurf Cascade trajectory markdown files from ~/.local/share/devin/cli/transcripts, ~/.config/devin, ~/.devin, ~/.codeium/windsurf/cascade (or DEVIN_HOME, DEVIN_SESSION_ID) are read. The subject is the session title or latest user prompt line, and the body is the last assistant text response.
• Freebuff / Codebuff: Chat transcripts from ~/.config/manicode/projects/<project>/chats/<chat-id>/chat-messages.json (or FREEBUFF_CONFIG_DIR, CODEBUFF_CONFIG_DIR, FREEBUFF_HOME, or FREEBUFF_SESSION_ID) are read. The subject is the first user prompt line (or session title from chat-meta.json), and the body is the last assistant text response.
• --agy-session <ID>, --claude-session <ID>, --codex-session <ID>, --devin-session <ID>, --freebuff-session <ID>, or --chat-session <ID> selects a specific session or transcript path.
• --message overrides the subject; the copied message remains the body.
• User file URIs like file:///Users/user/... are sanitized to ~/... to prevent leaking local user names, and references to the current repository directory are sanitized to ./.
• When Conventional Commits are enabled, commitlint rules shape the copied chat subject: inferring a missing conventional type: prefix from git changes, formatting casing, stripping forbidden trailing full stops, and fitting length limits. The assistant body is copied intact.
• If copying the log from the AI Agent fails, mm automatically falls back to generating the commit message from Git changes.

How changes are selected

1. If anything is staged, only staged changes are used.
2. Otherwise, tracked changes in the working tree are used and the commit is run as git commit -m MSG ..
3. Untracked files are ignored unless --add is passed.

This matches the original gacm behaviour. Use --print when you want to see the message without changing the repository.

commitlint configuration

mm reads the project's commitlint configuration and applies the rules which affect message generation. All formats supported by commitlint are handled:

• package.json or package.yaml with a commitlint field
• .commitlintrc, .commitlintrc.json, .commitlintrc.yaml, .commitlintrc.yml
• .commitlintrc.js, .commitlintrc.cjs, .commitlintrc.mjs
• .commitlintrc.ts, .commitlintrc.cts, .commitlintrc.mts
• commitlint.config.js, commitlint.config.cjs, commitlint.config.mjs
• commitlint.config.ts, commitlint.config.cts, commitlint.config.mts

The file is searched for from the current directory upwards, stopping at your home directory, in the same order as commitlint (cosmiconfig). Use mm --config path/to/file to point at a specific file.

JSON and YAML configs are parsed natively. JavaScript and TypeScript configs are evaluated with Node, and extends presets are resolved with @commitlint/load when it is installed. If it is not installed, the config file is imported directly and a warning is printed because presets cannot be resolved.

Applied rules:

Rule	Effect
type-enum	Restricts the generated type; falls back to an allowed type
type-case	Changes the type case, e.g. upper-case gives FEAT
type-empty	Requires a type, or removes it when it must be empty
type-max-length	Chooses a shorter type or truncates
scope-enum, scope-empty	Keeps or drops a scope such as deps
scope-case	Changes the scope case
header-max-length	Falls back to counted descriptions, then truncates
subject-max-length	Truncates the subject
header-full-stop, subject-full-stop	Removes a forbidden trailing full stop

Rules about bodies, footers, commit trailers and the case of free-form subjects are not applied to generated messages, because mm writes only a header. An explicit --message value is treated as an override and its prefix is kept. In chat modes (--chat, --opencode, --agy, --claude, --codex, --devin), header shaping rules (type prefix, casing, length, and trailing full stop removal) are applied to the subject, while copying the assistant body intact.

# .commitlintrc.yml
# rules:
# type-enum: [2, always, [feat, fix, chore]]
# header-max-length: [2, always, 72]
mm --print

Message rules

• One file: feat: create foo.rs, docs: update README.md, chore: delete old.txt, chore: rename a.rs to b.rs
• Two to four files: names are listed grouped by action, e.g. update src/main.rs and src/lib.rs or docs: update guide.md and create api.md
• Five or more files: counts are used, e.g. update 5 files
• The type is inferred from the changed paths. When changes disagree or a type cannot be determined, the default is chore
• Prefixes come from the path: docs (README, docs/, .rst), tests, CI, dependencies (build(deps)), build files, and configuration (chore)
• A new file with no other match is a feat
• Renames, moves and deletions are chore
• --message keeps your existing type prefix and appends your description after the generated one

Development

./test.sh

Or run individual commands:

cargo test
cargo fmt --check
cargo clippy --all-targets -- -D warnings

The crate only depends on serde_json and serde_norway for reading configuration files, and is split into modules which mirror the original TypeScript files:

Module	Original
git.rs	git/cli.ts, git/parseOutput.ts
paths.rs	lib/paths.ts, lib/commonPath.ts
conventional.rs	generate/convCommit.ts, generate/convCommitConstants.ts
message.rs	generate/action.ts, generate/count.ts, generate/message.ts
generate.rs	prepareCommitMsg.ts, generate/parseExisting.ts
cli.rs	cli/diffIndexGenerate.ts, cli/diffIndexGenerateCommit.ts
config.rs	New: reads mm.json settings
chat.rs	New: copies a title and last message from an OpenCode session
commitlint.rs	New: finds and loads the project's commitlint configuration
policy.rs	New: applies commitlint rules to a generated message
completions.rs	New: generates bash, zsh, and fish completion scripts

Differences from gacm

The selection of changes and the path-based message rules follow gacm. These parts differ on purpose:

• Messages use Conventional Commits by default, so a chore type is added when no type can be inferred. Set "conventionalCommits": false in mm.json to restore plain descriptions.
• --chat can copy the title and last assistant message from an OpenCode session instead of deriving the message from file paths.
• The commit editor is off by default; pass --edit to open it. -n and --no-edit are accepted so existing scripts keep working.
• --print (--dry-run) prints the message and never touches the repository.
• Paths are read with git diff-index --name-status -z, so spaces, quotes and unicode in file names do not need escaping.
• A repository without commits yet is supported by diffing against the empty tree.

License

MIT