gac: Skill for Claude Code

Code Quality Tools and Standards

When to Use

• Formatting code before committing
• Linting code for errors and style issues
• Type checking for correctness
• Reviewing or refactoring code

Makefile Targets (canonical)

make lint and make format run four tools, not just ruff:

make format     # ruff check --fix + ruff format + prettier --write + markdownlint --fix
make lint       # ruff check + ruff format --check + prettier --check + markdownlint --check
make type-check # mypy
make test       # uv run -- pytest

Running uv run ruff check . alone does NOT equal make lint. CI runs all four.

Individual Tools

uv run ruff check src/           # Lint
uv run ruff format src/          # Format
uv run mypy src/                 # Type check

Coding Standards

Type Annotations (required)

def parse_response(response: dict[str, Any]) -> str | None:
    """Parse API response and extract content."""
    message = response.get("message", {})
    return message.get("content")

Naming

• Modules/functions: snake_case
• Classes: CapWords
• Constants: UPPER_SNAKE_CASE

Line Length: 120 characters max

Docstrings: Google-style

def generate(model: str, messages: list[dict]) -> tuple[str, int, int, int, int]:
    """Generate text using the AI provider.

    Args:
        model: Model name to use.
        messages: List of message dictionaries.

    Returns:
        Tuple of (content, input_tokens, output_tokens, input_cost, output_cost).
    """

File Size: 600 lines max

Split when exceeded — but don't split purely for line count if it hurts cohesion.

Pre-commit Workflow

# 1. Make changes
# 2. Format + lint
make format
make lint
# 3. Type check
make type-check
# 4. Test
make test
# 5. Commit with gac (scope + yes)
gac -sy

Note: -s is --scope (infers commit scope), -y is --yes (skips confirmation). Not "short mode".

Checklist

[ ] make format run?
[ ] make lint passes? (all 4 tools)
[ ] make type-check passes?
[ ] make test passes?
[ ] File length under 600 lines?
[ ] Type annotations on all functions?
[ ] Docstrings on public functions?