git-ai-commit

Generate Git commit messages from staged diffs using your preferred LLM CLI.

git-ai-commit does not talk to LLM APIs directly. Instead, it delegates generation to existing LLM CLIs such as Claude Code, Gemini, or Codex, so no API keys, SDKs, or vendor-specific integrations are required.

Install

Package managers:

Homebrew:

brew tap takai/tap
brew install git-ai-commit

mise:

mise use -g github:takai/git-ai-commit@latest

Build from source (outputs to bin/):

make build

Put bin/git-ai-commit on your PATH to enable git ai-commit.

Usage

git ai-commit [options]

Common options:

• --context VALUE Additional context for the commit message
• --context-file VALUE File containing additional context
• --prompt VALUE Bundled prompt preset: default, conventional, gitmoji, karma
• --prompt-file VALUE Path to a custom prompt file
• --engine VALUE Override engine name
• --amend Amend the previous commit
• -a, --all Stage modified and deleted files before generating the message
• -i, --include VALUE Stage specific files before generating the message
• -x, --exclude VALUE Hide specific files from the diff for message generation
• --debug-prompt Print the prompt before executing the engine
• --debug-command Print the engine command before execution
• -h, --help Show help

Configuration

Configuration is layered, allowing global defaults with per-repository overrides:

1. User config: ~/.config/git-ai-commit/config.toml
2. Repo config: .git-ai-commit.toml at the repository root
3. Command-line flags

This makes it easy to keep personal preferences (engine, style) while enforcing repository-specific commit rules without relying on hosted services. Repository config is applied only after an initial trust prompt.

Example: Use Codex with Conventional Commits by default

engine = "codex"
prompt = "conventional"

Supported settings:

• engine Default engine name (string)
• prompt Bundled prompt preset: default, conventional, gitmoji, karma
• prompt_file Path to a custom prompt file (relative to the config file)
• engines.<name>.args Argument list for the engine command (array of strings)
• filter.max_file_lines Maximum lines per file in diff (default: 100)
• filter.exclude_patterns Additional glob patterns to exclude from diff
• filter.default_exclude_patterns Override built-in exclude patterns

Engines

git-ai-commit treats LLMs as external commands, not as APIs. This design avoids direct network calls and API key management, and lets you reuse your existing LLM CLI setup.

Supported engines:

• claude
• gemini
• codex

If no engine is configured, auto-detection tries commands in this order: claude → gemini → codex. The first available command is used.

Any other engine name is treated as a direct command and executed with the prompt on stdin.

Example: Use ollama with gemma3:4b

engine = "ollama"

[engines.ollama]
args = ["run", "gemma3:4b"]

Prompt presets

Bundled presets live in internal/config/assets/:

• default – Commit messages aligned with the recommendations in Pro Git
• conventional – Conventional Commits format
• gitmoji – gitmoji-based commit messages
• karma – Karma-style commit messages

Custom Prompts

Example: Use a custom prompt file

engine = "claude"
prompt_file = "prompts/commit.md"

Note: prompt and prompt_file are mutually exclusive within the same config file. If both are set, an error is returned. When settings come from different layers (user config vs repo config), the later layer wins.

Diff Filtering

When the staged diff is large, it can exceed LLM context limits or degrade commit message quality. git-ai-commit automatically filters the diff to help LLMs focus on meaningful changes.

Default behavior:

• Each file is limited to 100 lines (configurable via filter.max_file_lines)
• Lock files and generated files are excluded by default

Default exclude patterns:

• **/*.lock, **/*-lock.json, **/*.lock.yaml, **/*-lock.yaml, **/*.lockfile
• **/*.min.js, **/*.min.css, **/*.map
• **/go.sum

Example: Customize filtering

[filter]
max_file_lines = 300

# Add patterns to exclude (merged with defaults)
exclude_patterns = [
    "**/vendor/**",
    "**/*.generated.go",
    "**/dist/**"
]

# Or replace defaults entirely
# default_exclude_patterns = ["**/my-lock.json"]

Claude Code Plugin

If you use Claude Code, you can integrate git-ai-commit as a plugin for a more convenient workflow.

Installation

/plugin marketplace add takai/git-ai-commit
/plugin install ai-commit@git-ai-commit-plugins

Commands

• /ai-commit:staged - Commits only the currently staged changes
• /ai-commit:all - Stages all pending changes and commits as a single commit
• /ai-commit:organize - Organizes pending changes into multiple atomic commits

Acknowledgements

This tool was inspired by how @negipo used a tool like this in his workflow to make his work much more efficient.