# Python Review > Python code review guidelines for the Cog SDK Use when this capability is needed. - Skill: `tomevault-io/python-review` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/python-review` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/python-review/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/python-review --- ## Python review guidelines This project uses Python for the SDK (`python/cog/`) which defines the predictor interface, type system, and HTTP/queue server. ### What linters already catch (skip these) ruff handles pycodestyle (E), Pyflakes (F), isort (I), warnings (W), bandit (S), bugbear (B), and annotations (ANN). Don't flag issues these would catch. ### What to look for **Type annotations** - Required on all function signatures - Use `typing_extensions` for backward compatibility - Avoid `Any` where a concrete type is possible - Check that type annotations actually match runtime behavior **Compatibility** - Must support Python 3.10 through 3.13 - Watch for syntax/stdlib features only available in newer versions - `from __future__ import annotations` if using newer annotation syntax **Error handling** - No bare `except:` or `except Exception:` that swallows everything - Exceptions should have descriptive messages - Resource cleanup with context managers, not try/finally when avoidable **Async patterns** - Tests use pytest-asyncio -- async tests need proper fixtures - Watch for blocking calls inside async functions - Proper cleanup of async resources (aclose, async context managers) **Predictor interface** - `base_predictor.py` is the core interface -- changes here affect all users - `types.py` defines input/output types -- check backward compatibility - Server code in `python/cog/server/` handles HTTP -- watch for request handling bugs **Testing** - Uses pytest with fixtures - tox runs tests across Python 3.10-3.13 - Test isolation: don't rely on global state or test ordering --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/replicate) — claim your Tome and manage your conversions.