python-patterns

Guide Python 3.12+ codebases through modern typing, Pydantic v2, and async patterns.

11|1|Updated Feb 9, 2026
One-click install
npx skills add https://github.com/mindcockpit-ai/cognitive-core --skill python-patterns-mindcockpit-ai
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: python-patterns
Source: https://github.com/mindcockpit-ai/cognitive-core/tree/main/.claude/skills/python-patterns
Command: npx skills add https://github.com/mindcockpit-ai/cognitive-core --skill python-patterns-mindcockpit-ai

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Provides concise, practical guidance to eliminate legacy typing, incorrect Pydantic v1 patterns, unsafe async usage, and other common anti-patterns that lower code quality and increase maintenance burden.

Core Features & Use Cases

  • Modern typing and generics: Clear recommendations for PEP 695 style type aliases, built-in generics, and nullable union usage to improve type safety and readability.
  • Pydantic v2 best practices: Guidance on using model_config, field validators, and discriminated unions to migrate from v1 patterns and avoid common pitfalls.
  • Async, dataclasses, and testing: Patterns for async context managers, TaskGroup usage, immutable/dataclass value objects, and pytest techniques to build robust async code and reliable tests.
  • Use Case: Ideal for engineers migrating a codebase to Python 3.12+, auditing repositories for typing and Pydantic anti-patterns, or establishing team-wide idioms.

Quick Start

Ask the assistant to review a Python file and provide fixes and explanations for modern 3.12+ typing, Pydantic v2 usage, async patterns, dataclass practices, and common anti-patterns.

Frequently Asked Questions about python-patterns

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I migrate Pydantic v1 models to v2 using the new model_config and validators?

Migrate Pydantic v1 models to v2 by replacing inner Config classes with model_config, applying field validators, and utilizing discriminated unions to avoid common pitfalls and ensure correct validation.

What's the best way to apply PEP 695 type hints and generics in Python 3.12?

Apply PEP 695 type hints in Python 3.12 by using the new style type aliases, built-in generics, and nullable union usage to improve type safety and readability.

How do I use async context managers and TaskGroup for robust asynchronous programming?

Build robust asynchronous programming by implementing async context managers and utilizing TaskGroup usage to manage concurrent tasks safely and avoid unsafe async usage.

Can I use structural pattern matching and dataclasses to create immutable value objects in Python?

Yes, you can use structural pattern matching alongside immutable dataclass value objects to improve code correctness and maintainability in Python 3.12+.

Why does my codebase have anti-patterns after upgrading to Python 3.12, and how do I fix them?

Legacy typing and unsafe async usage create anti-patterns after upgrading to Python 3.12; fix them by applying modern idiomatic patterns, type hints, and testable exception handling.

Do I need pytest techniques specifically for testing async code and testable exception handling?

Yes, utilizing specific pytest techniques is required to build reliable tests for async code and establish testable exception handling in modern Python workflows.