Commit Writer

A standalone golang program that

• Reads a staged git diff
• Sends it to a "factual summarizer model" (default: gemma3:4B)
• Sends a summary + tone instruction to a "styling model" (default: mistral:7b) to rewrite the summary in the given tone
• Prints the final commit message to stdout and optionally writes it to a commit message file (for git hook usage)

Build

go build -o commit-writer main.go

Usage Examples

Basic Usage

# Stage your changes
git add -A

# Generate commit message with default tone
./commit-writer

# Use a specific tone
./commit-writer --tone "increasingly insane Victorian author"

# Clean output without labels (easy to copy/paste)
./commit-writer --tone "chaotic, wild, funny" --no-labels

# Use different models
./commit-writer --summ-model "llama3:8b" --style-model "mistral:7b" --tone "pirate speak"

# Timeout flag for larger models
./commit-writer --timeout 600 --tone "professional"

# Title only mode
./commit-writer --title-only

# Title only with custom tone
./commit-writer --title-only --tone "professional, concise"

# Custom Ollama URL
./commit-writer --ollama "http://192.168.1.100:11434/api/generate" --tone "professional"

Direct Commit (One-liner)

# Stage and commit in one command
git add -A && git commit -m "$(./commit-writer --no-labels --tone 'professional')"

# Or with error handling
git add -A && git commit -m "$(./commit-writer --no-labels)" || echo "Commit failed"

# Using default tone
git add . && git commit -m "$(./commit-writer --no-labels)"

# Quick commit with custom tone
git commit -am "$(./commit-writer --no-labels --tone 'concise and technical')"

Advanced: Save/Reuse Summary for Faster Tone Iteration

You can save the factual summary from the first LLM and reuse it to quickly try different tones:

# Step 1: Generate and save the factual summary
git add -A
./commit-writer --save-summary summary.txt --tone "professional"

# Step 2: Iterate on different tones using the saved summary (much faster!)
./commit-writer --load-summary summary.txt --tone "increasingly insane Victorian author"
./commit-writer --load-summary summary.txt --tone "pirate speak"
./commit-writer --load-summary summary.txt --tone "overly dramatic Shakespeare"

# Step 3: You can also write your own summary and apply tone to it
echo "Add user authentication\n\nImplemented JWT-based auth" > my-summary.txt
./commit-writer --load-summary my-summary.txt --tone "chaotic, wild, funny"

This workflow is useful for:

1. Reviewing the factual summary before applying tone
2. Faster iteration on different tones without re-analyzing the diff
3. Manual control - write your own summary and let the style model add flair

Git Hook Setup

Install as a prepare-commit-msg hook to automatically generate commit messages:

# Copy the binary to your hooks directory
cp ./commit-writer .git/hooks/commit-writer

# Create the prepare-commit-msg hook
cat > .git/hooks/prepare-commit-msg << 'EOF'
#!/bin/bash
# Auto-generate commit messages with commit-writer
# $1 is the path to the commit message file

TONE="${COMMIT_TONE:-chaotic, wild, funny}"
.git/hooks/commit-writer --hook "$1" --tone "$TONE" --force
EOF

# Make both executable
chmod +x .git/hooks/prepare-commit-msg
chmod +x .git/hooks/commit-writer

Now when you run git commit, the message will be auto-generated:

# Stage changes and commit (message auto-generated)
git add -A
git commit

# Override the tone with environment variable
COMMIT_TONE="professional and concise" git commit

# Or edit the generated message before committing
git commit  # Opens editor with generated message

Alternative Hook: Append suggestion as comment

If you prefer to review the suggestion before using it:

cat > .git/hooks/prepare-commit-msg << 'EOF'
#!/bin/bash
# Add commit-writer suggestion as a comment
.git/hooks/commit-writer --hook "$1" --tone "chaotic, wild, funny"
EOF

chmod +x .git/hooks/prepare-commit-msg

This appends the suggestion as a commented section in your commit message editor

Creative Tone Examples

# Professional & concise
./commit-writer --tone "professional, concise, technical"

# Fun and creative
./commit-writer --tone "pirate captain documenting ship modifications"
./commit-writer --tone "overly dramatic Shakespeare"
./commit-writer --tone "excited scientist making a breakthrough"
./commit-writer --tone "noir detective solving a case"
./commit-writer --tone "sports commentator narrating a game"

# Specific styles
./commit-writer --tone "haiku poetry"
./commit-writer --tone "military briefing"
./commit-writer --tone "cooking recipe instructions"

# Combining with save/load for experimentation
./commit-writer --save-summary sum.txt --tone "professional"
./commit-writer --load-summary sum.txt --tone "1920s gangster"
./commit-writer --load-summary sum.txt --tone "confused time traveler"

Debugging and Development

# Enable debug logging to see what's happening
./commit-writer --debug --tone "professional"

# Test with different model combinations
./commit-writer --summ-model "codellama:7b" --style-model "llama3:8b" --debug

# Save summary for manual review before styling
./commit-writer --save-summary review.txt --tone "professional"
cat review.txt  # Review the factual summary
# Edit review.txt manually if needed
./commit-writer --load-summary review.txt --tone "chaotic, wild, funny"

Quick flags & notes

• --ollama : Ollama API URL (or set OLLAMA_URL env var). Default: http://localhost:11434/api/generate
• --summ-model : Summarizer model (default gemma3:4B)
• --style-model : Styling model (default mistral:7b)
• --tone : Tone description passed to the stylistic model
• --hook : Path to commit message file to write/append the suggestion
• --force : Overwrite the --hook file instead of appending
• --debug : Enable debug logging (prints additional info to stderr)
• --no-labels : Remove "Title:" and "Body:" labels from output for easier copy/paste
• --save-summary : Save the factual summary to a file (useful for review or reuse with different tones)
• --load-summary : Load a previously saved summary and skip the first LLM (fast tone iteration)
• --timeout : Sets the timeout in seconds for the HTTP call to the Ollama API. Default: 300 (5 minutes).
• --title-only : Outputs only a title instead of the normal title+body commit message. Default: false

Practical Workflows

Workflow 1: Quick one-liner commits

Perfect for small changes when you want speed:

git commit -am "$(./commit-writer --no-labels --tone 'concise')"

Workflow 2: Review before committing

Generate, review, then commit manually:

./commit-writer --tone "professional"
# Review the output, then copy/paste or:
./commit-writer --no-labels | pbcopy  # macOS
./commit-writer --no-labels | xclip -selection clipboard  # Linux
git commit  # Paste the message

Workflow 3: Iterate on tone

When you want to experiment with different tones:

# Generate and save factual summary once
./commit-writer --save-summary .commit-summary.txt --tone "professional"

# Try different tones quickly
./commit-writer --load-summary .commit-summary.txt --tone "pirate speak" --no-labels
./commit-writer --load-summary .commit-summary.txt --tone "haiku" --no-labels
./commit-writer --load-summary .commit-summary.txt --tone "Shakespearean" --no-labels

# Pick your favorite and commit
git commit -m "$(./commit-writer --load-summary .commit-summary.txt --tone 'pirate speak' --no-labels)"

Workflow 4: Git hook automation

Set up the hook once, then commits are automatic:

# One-time setup (see Git Hook Setup section above)
# ...

# Daily usage - just commit normally
git add -A
git commit  # Message auto-generated!

# Override tone when needed
COMMIT_TONE="very serious and professional" git commit

Workflow 5: Manual summary + AI styling

Write your own factual summary, then let AI add flair:

# Write your own summary
cat > my-commit.txt << 'EOF'
Add user authentication

Implemented JWT-based authentication with refresh tokens.
Added login and logout endpoints. Updated user model.
EOF

# Apply creative tone to your summary
./commit-writer --load-summary my-commit.txt --tone "excited product launch announcement" --no-labels

Workflow 6: Interactive confirmation with gum

For interactive workflows where you want to review and approve before committing (requires gum):

# Generate message, display it, confirm, then commit
MSG="$(./commit-writer --tone "chaotic devops engineer" --no-labels --save-summary summary.txt)" && echo "$MSG" && gum confirm "Accept?" && git commit -m "$MSG"

# Reuse summary with different tone
MSG="$(./commit-writer --tone "Eeyore from Winnie the Pooh" --no-labels --load-summary summary.txt)" && echo "$MSG" && gum confirm "Accept?" && git commit -m "$MSG"

This workflow:

• Generates the commit message with your chosen tone
• Displays it for review (echo "$MSG")
• Prompts for confirmation (gum confirm)
• Only commits if you approve
• Can quickly iterate on different tones by reusing saved summaries

Development Notes

Build with modules enabled (there is a minimal go.mod included). Run go vet and golangci-lint run during development to catch issues.