Python backend (FastAPI + Pydantic v2 + Alembic) Activation cues Use this skill when the task involves: 1) new or modified FastAPI endpoints, routers, dependencies, middleware 2) request/response validation, schema design, OpenAPI correctness (Pydantic v2) 3) database schema changes (Alembic revisions) 4) backend logging and request tracing 5) ETL / parsers / import pipelines with memory constraints and “bad rows” reporting Operating principles (agent workflow) 1) Start with a short plan before editing code. Prefer file-path-specific steps and repository-aligned patterns. 2) Ask up to 1–3 cla…