LLM-powered git commit message generator

Generates conventional commits from git diffs using Claude AI or any OpenAI-compatible API.
Automatic changelog maintenance, multi-commit composition, and full history rewriting.

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Features

• Conventional commits — Generates properly formatted commit messages with type, scope, and past-tense summary (≤72 chars)
• Automatic changelogs — Maintains CHANGELOG.md following Keep a Changelog format with monorepo support
• Compose mode — Splits large staged changes into multiple logical atomic commits
• Rewrite mode — Converts entire git history to conventional commits (with automatic backup)
• Map-reduce analysis — Parallel per-file analysis for large commits without truncation
• Any LLM provider — Works with Anthropic, OpenAI, OpenRouter, or any OpenAI-compatible API

Quick Start

# Install
cargo install llm-git

# Configure (pick one)
export LLM_GIT_API_KEY=your_anthropic_key                    # Direct Anthropic
export LLM_GIT_API_URL=https://openrouter.ai/api/v1          # OpenRouter
litellm --port 4000                                           # Local proxy (default)

# Use
git add .
lgit                    # Analyze, update changelog, commit
lgit --dry-run          # Preview without committing
lgit --compose          # Split into multiple commits

Usage

Basic Commands

lgit                                # Analyze staged changes and commit
lgit --dry-run                      # Preview message without committing
lgit --copy                         # Copy message to clipboard
lgit -p                             # Commit and push
lgit -S                             # GPG sign the commit
lgit -s                             # Add Signed-off-by trailer
lgit --amend                        # Amend the previous commit
lgit > msg.txt                      # Save raw message to file (auto-detected pipe mode)
lgit --dry-run | git commit -F -    # Generate message and commit with custom git flags

# Modes
lgit --mode=unstaged                # Preview unstaged changes (no commit)
lgit --mode=commit --target=HEAD~1  # Analyze a specific commit

# Models
lgit -m opus                        # Use Opus for analysis (more capable)
lgit -m sonnet                      # Use Sonnet (default)

# Context
lgit Fixed regression from PR #123  # Add context via trailing text
lgit --fixes 123 456                # Add "Fixes #123, #456" to body
lgit --breaking                     # Mark as breaking change

Compose Mode

Split staged changes into multiple logical commits:

lgit --compose                      # Propose and create atomic commits
lgit --compose --compose-preview    # Preview splits without committing
lgit --compose --compose-max-commits 5
lgit --compose --compose-test-after-each

Rewrite Mode

Convert repository history to conventional commits:

lgit --rewrite                      # Rewrite full history (creates backup)
lgit --rewrite --rewrite-preview 10 # Preview first 10 commits
lgit --rewrite --rewrite-dry-run    # Show all changes without applying
lgit --rewrite --rewrite-start main~50  # Rewrite last 50 commits only
lgit --rewrite --rewrite-parallel 20    # 20 concurrent API calls

Automatic Changelog

lgit automatically maintains CHANGELOG.md files when committing:

• Auto-detection — Finds all CHANGELOG.md files in your repository
• Monorepo support — Routes changes to the correct changelog based on file paths
• Deduplication — Skips entries semantically similar to existing ones
• Category mapping — Maps commit types to sections (Added, Fixed, Changed, etc.)

project/
├── CHANGELOG.md              ← covers: src/, docs/
├── packages/
│   ├── core/
│   │   └── CHANGELOG.md      ← covers: packages/core/**
│   └── cli/
│       └── CHANGELOG.md      ← covers: packages/cli/**

Disable with --no-changelog or changelog_enabled = false in config.

Configuration

Create ~/.config/llm-git/config.toml:

# API
api_base_url = "http://localhost:4000"    # Default: LiteLLM proxy
api_key = "sk-..."                        # Or use LLM_GIT_API_KEY env var

# Model
model = "claude-sonnet-4-5"               # Default model for all API calls

# Commit message limits
summary_guideline = 72                    # Target length
summary_soft_limit = 96                   # Triggers retry
summary_hard_limit = 128                  # Absolute max

# Features
changelog_enabled = true
map_reduce_enabled = true                 # Parallel analysis for large commits
temperature = 0.2                         # Structured-output-first, then tools, then JSON content parse

# Commit signing
gpg_sign = false                          # GPG sign commits by default (-S)
signoff = false                           # Add Signed-off-by trailer by default (-s)

Provider Examples

Anthropic Direct:

api_base_url = "https://api.anthropic.com/v1"
api_key = "sk-ant-..."

OpenRouter:

api_base_url = "https://openrouter.ai/api/v1"
api_key = "sk-or-..."
model = "anthropic/claude-sonnet-4.5"

OpenAI:

api_base_url = "https://api.openai.com/v1"
api_key = "sk-..."
model = "gpt-4o"

The client now prefers provider-native structured outputs, falls back to tool calling when unsupported, and only then falls back to parsing JSON content from the model response. Anthropic models only use structured outputs on the official Anthropic base URL; routed Anthropic models fall back directly to tool calling.

Commit Types

Customize commit type classification:

[types.feat]
description = "New public API or user-observable behavior change"
diff_indicators = ["pub fn", "pub struct", "export function"]

[types.fix]
description = "Fixes incorrect behavior"
diff_indicators = ["unwrap() → ?", "bounds check", "error handling"]

[types.refactor]
description = "Internal restructuring with unchanged behavior"
hint = "If behavior changes, use feat instead."

Changelog Categories

[[categories]]
name = "Breaking"
header = "Breaking Changes"
match.body_contains = ["breaking", "incompatible"]

[[categories]]
name = "Added"
match.types = ["feat"]

[[categories]]
name = "Fixed"
match.types = ["fix"]

[[categories]]
name = "Changed"
default = true

Environment Variables

Variable	Description	Default
LLM_GIT_API_URL	API endpoint	http://localhost:4000
LLM_GIT_API_KEY	API key	none
LLM_GIT_CONFIG	Config file path	~/.config/llm-git/config.toml
LLM_GIT_VERBOSE	Debug output	false

Installation

From crates.io

cargo install llm-git

From source

git clone https://github.com/can1357/llm-git.git
cd llm-git
cargo install --path .

Prerequisites

• Rust nightly toolchain
• Git
• API access (Anthropic, OpenAI, OpenRouter, or local LiteLLM proxy)

License

MIT