Python Engineering Standards

For the full rationale and edge cases behind the defaults below, load the python-engineering:standards-for-python-development skill.

Standing Defaults (apply to every Python task)

Code Quality

• Python 3.11+ native types: list[str], str | None, Self, TypeAlias
• Google-style docstrings (Args/Returns/Raises)
• SOLID principles as active design guidance, not checklist items
• Functions under 50 lines; max 3 nesting levels
• __all__ in public modules
• No Any, broad object, or unchecked cast() in internal code
• Code smells are design signals to investigate, not noise to suppress
• Expand acronyms in public names: greatest_common_divisor() not gcd(); domain acronyms (URL, API, SQL, HTTP, JSON, XML) are exempt; see references/python3-standards.md §1.5