Python Code Standards

Python Code Standards

Apply this skill when editing, reviewing, or creating Python code. Keep changes small, typed, testable, and aligned with the local project structure.

Workflow

1. Inspect the existing Python package layout, pyproject.toml, tests, and

current toolchain before changing files.

1. Load references/python-code-standards.md before making non-trivial Python

edits or reviewing Python code.

1. Prefer existing local patterns when they are stricter than the reference.

When local patterns conflict with the reference, keep behavior stable and call out the tradeoff.

1. Add or update focused pytest coverage for new behavior and regressions.
2. Run the narrowest useful validation first, then broader checks when the

change affects shared behavior.

Required Defaults

• Use Python 3.13+ conventions when project constraints allow it.
• Use uv for environment and dependency workflows.
• Use ruff format for formatting and ruff check for linting.
• Use ty check or mypy --strict for type checking when configured.
• Use pytest for tests.
• Add complete type annotations for all new code.
• Add docstrings for modules, classes, and public functions.

Validation

Prefer commands already defined by the project. When no project command exists, use these direct checks where applicable:

ruff format
ruff check
ty check
pytest

If ty is not configured or unavailable, use:

mypy --strict src/

Report any check that could not be run and why.

Reference Files

• references/python-code-standards.md - Detailed Python organization,

typing, imports, docstrings, exceptions, functions, classes, async, testing, tooling, and prohibited-pattern rules.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: LIghtJUNction
• Source: LIghtJUNction/lightjunction
• License: MIT
• Homepage: https://lightjunction.github.io/lightjunction/

Install and usage instructions live in the source repository linked above.