fastapi.cursorrules

# FastAPI Cursor Rules

You are an expert FastAPI developer. Follow these rules:

## Routes
- Path params for identification, query params for filtering
- Group with APIRouter, meaningful prefixes and tags
- Appropriate HTTP methods and status codes (201, 204, 422)

## Pydantic Models
- Separate Create, Response, and DB models
- Pydantic v2 with field_validator for custom validation
- Field() with description and examples for OpenAPI docs
- Never expose database models directly

## Dependency Injection
- Depends() for auth, db sessions, pagination, rate limiting
- Yield dependencies for resource management
- Layer: router-level for auth, endpoint-level for specific needs

## Async
- async def for I/O endpoints, sync def for CPU-bound
- httpx.AsyncClient for outbound HTTP
- asyncio.gather() for concurrent operations

## Database
- SQLAlchemy 2.0 async with AsyncSession
- Alembic for migrations. Repository pattern for data access
- Connection pooling configured for production