transcription/.github/skills/python-code-reviewer/skill.md

name, description

name	description
python-code-reviewer	Perform an evidence-based, senior architect code review for Python codebases using FastAPI, NiceGUI, SQLModel, SQLAlchemy, Pydantic V2, asyncio, and OpenRouter. Use when asked to review Python repositories, perform architectural or code audits, or evaluate code against Python 3.12+ best practices.

Python Code Reviewer

Perform thorough, evidence-based code reviews for Python projects. Every finding must cite concrete file paths and line ranges, avoid speculation, and include recommended fixes.

When to Use

• Performing an architectural or code quality review of a Python codebase.
• Auditing applications using FastAPI, NiceGUI, SQLModel/SQLAlchemy, Pydantic V2, or asyncio workers.
• Generating structured Markdown review reports in ./docs.

Technical Stack Scope

• Runtime: Python 3.12+
• Web Application: FastAPI and NiceGUI
• Persistence: SQLModel, SQLAlchemy (SQLite and PostgreSQL support)
• Validation & Settings: Pydantic V2 and pydantic-settings
• Concurrency: Python asyncio workers
• Vision/LLM Integration: OpenRouter / provider adapters
• Quality & Testing: pytest, pytest-asyncio, Ruff, and ty

Review Workflow

1. Map the Repository First: Inspect entry points, package layout, configurations, dependency manifests, and any project-specific rule files (AGENTS.md, CLAUDE.md, .github/instructions/). Project-specific conventions override generic advice.
2. Read Representative Modules: Sample across all layers (routes/pages, UI components, services, workers, persistence, provider adapters, settings, tests) before drawing conclusions.
3. Verify Claims: Run or reference project tooling (ruff check, ty, pytest) rather than guessing.
4. Prioritize Hot Paths: Focus deeply on request handling, database sessions, background workers, and external API calls.
5. Enforce Read-Only Safety: Do not modify code unless explicitly instructed.

Core Review Areas

1. Python Best Practices (3.12+)

• Type Annotations: Ensure completeness, modern syntax (X | None, builtin generics, Self, type statements), and avoid unparameterized containers or bare Any.
• Error Handling: Identify bare/broad except, swallowed exceptions, missing raise ... from, and exceptions used for control flow.
• Resource Management: Verify context managers for files, DB sessions, HTTP clients, and locks. Check for leaked tasks or connections.
• Data Modeling: Check proper use of dataclasses vs. Pydantic models vs. dictionaries. Eliminate mutable default arguments and stringly-typed payloads.
• Idioms & Clean Code: Verify pathlib usage over os.path, comprehensions vs manual loops, removal of dead code, and elimination of magic numbers.

2. FastAPI

• Dependency Injection: Verify Depends is used for shared resources (DB sessions, settings, clients) rather than global singletons.
• Route Design: Validate HTTP verbs, status codes, path/query/body typing, response_model, and domain-based router organization.
• Lifecycle & Concurrency: Ensure lifespan handlers are used instead of deprecated @app.on_event. Flag blocking synchronous calls in async def endpoints.

3. NiceGUI

• Separation of Concerns: Ensure UI components delegate business logic and persistence to service layers.
• Client State Handling: Verify correct use of client-scoped state vs global state to avoid state leaks across sessions.
• Async Execution: Check for blocking operations on the UI event loop and unbounded timers/pollers.

4. Persistence (SQLModel / SQLAlchemy)

• Session Lifecycle: Enforce one session per request/unit of work with explicit commit/rollback/close boundaries.
• Query Optimization: Detect N+1 patterns, missing eager loads (selectinload/joinedload), queries inside loops, and unindexed filters.
• Cross-Dialect Portability: Check compatibility for both SQLite (WAL mode, pragmas) and PostgreSQL (JSONB, locking, autoincrement).

5. Pydantic V2 & Settings

• V2 Migration: Flag legacy V1 patterns (@validator, Config class, .dict(), parse_obj) and use V2 equivalents (@field_validator, model_config = ConfigDict(...), model_dump()).
• Settings Management: Ensure BaseSettings is the single source of truth without scattered os.getenv calls or committed secrets.

6. Concurrency & Asyncio Workers

• Task Lifecycle: Flag unreferenced create_task calls that risk garbage collection, missing cancellation handling, and lack of graceful shutdown.
• Backpressure & Synchronization: Check for appropriate use of asyncio.Queue, TaskGroup, Lock, and backoff retries.

7. Provider Adapters (OpenRouter / APIs)

• Adapter Encapsulation: Verify provider-specific details (headers, model names, payload formats) do not leak into UI or business logic.
• Client Lifecycle: Reuse shared AsyncClient instances with proper connection pooling and timeouts. Validate API responses using Pydantic schemas.

8. Testing & Quality Tooling

• Test Isolation: Verify tests do not rely on live external services, real clocks, or shared global state.
• Async Test Setup: Check pytest-asyncio configuration and fixture lifecycle.

9. Duplication & Consolidation

• Identify repeated code blocks, candidate helper abstractions, divergent patterns for identical operations, and duplicated domain constants.

Output Report Structure & Template

Generate Markdown reports in ./docs following this exact template structure:

# Architecture & Code Review Report

**Repository Target:** `project-root/`
**Target Stack:** Python 3.12+ | FastAPI | NiceGUI | SQLModel/SQLAlchemy | Pydantic V2 | asyncio | OpenRouter

---

## 1. Executive Summary
- 5-10 bullets on overall health, top risks, and high-leverage refactors.

---

## 2. Findings by Severity

### Critical Severity
#### [CRIT-01] Title
- **Location:** `path/to/file.py:lines`
- **Problem & Consequence:** Concrete consequence, not a style opinion.
- **Recommendation:** Fix with before/after sketch.
- **Effort:** S / M / L

### High Severity
#### [HIGH-01] Title
...

### Medium Severity
#### [MED-01] Title
...

### Low Severity
#### [LOW-01] Title
...

---

## 3. Stack-Specific Analysis
- Python 3.12+ Best Practices
- FastAPI
- NiceGUI
- SQLModel & SQLAlchemy
- Pydantic V2 & Settings
- Asyncio Workers
- OpenRouter / Adapter Boundary
- Testing & Quality Tooling

---

## 4. Duplication & Consolidation Report
| Pattern / Duplication | Locations | Proposed Canonical Home | Estimated Lines Removed |
| :--- | :--- | :--- | :--- |

### Proposed Canonical Abstractions
- Code signatures and implementation homes.

---

## 5. Prioritized Action Plan
1. **Phase 1: Quick Wins (PR 1-2)**
2. **Phase 2: Reliability & Concurrency (PR 3-4)**
3. **Phase 3: Consolidation & Refactoring (PR 5-6)**

---

## 6. Preserved Strengths
- Existing patterns worth maintaining.