Python Style & Quality Gate (Typing • Docstrings • PEP 8/Black • Tests)

Purpose

When writing or modifying Python, apply a “quality gate” aligned to this rule-set:

• Use type hints consistently (including return types), prefer from __future__ import annotations.
• Write concise docstrings for public modules/classes/functions (one-line summary + key params/returns/raises) in Google style.
• Follow PEP 8; Black formatting; keep functions small and cohesive.
• Provide unit tests that exercise the documented behavior and typed signatures.

When to activate

Activate this skill when:

• Editing/creating **/*.py, or
• The user requests: typing, annotations, docstrings, PEP 8, Black, refactor-for-clarity, unit tests, pytest.