python-engineering

Performs holistic code review after feature implementation. Checks design quality, typed-boundary compliance, testing adequacy, and maintainability.

Creates, enhances, and reviews Python CLI code using Typer and Rich — use for CLI tools, scripts with progress bars or tables, async processing, modernizing existing CLIs, or any Python implementation task.

Produces architecture specifications for Python CLI applications — 11-section design-first specs covering Executive Summary, Architecture Overview, Technology Stack, Component Design, Data Architecture, Type System Design, Security Architecture, Testing Architecture, Distribution Architecture, ADRs, and Scalability Strategy. Activates on architecture planning requests for new CLI tools or major feature additions. Produces WHAT to build (interfaces, schemas, contracts); python-cli-architect handles the HOW (implementation).

Creates, reviews, or modernizes Python 3.11+ pytest test suites. Expert in fixture design, parametrization, hypothesis property-based tests, and coverage strategy.

Semantic search over Python codebases for finding relevant patterns, implementations, and usage examples.

Use when analyzing failing test cases to determine whether failures indicate genuine bugs or test implementation issues. Activates on "analyze failing tests", "debug test failures", "investigate test errors", or when provided with specific failing test names or output. Applies balanced investigative reasoning — does not auto-fix tests without establishing root cause.

Use when building async APIs, concurrent systems, or I/O-bound Python applications requiring non-blocking operations. Covers asyncio, async/await patterns, task scheduling, synchronization primitives, and high-performance concurrent programming.

Use when improving Python code quality through focused cleanup, smell investigation, modernization, and typed-boundary hardening. Invoke for refactoring tasks, dead code removal, or modernization passes.

Use when reviewing pytest test suites for coverage, isolation, mock usage, naming conventions, or completeness. Activates on requests like "review test coverage", "audit test quality", or "check tests for completeness". Performs thorough checklist-driven review for test isolation, mock correctness, AAA pattern adherence, and naming standards.

Use when creating a new feature task with structured tracking, phases, and documentation. Activates on "create a feature task", "set up development tracking", or "plan a feature implementation" requests. Produces a comprehensive feature development task with acceptance criteria, phase breakdown, and tracking artifacts ready for SAM pipeline execution.