FastAPI AI Patterns

Opinionated, production-calibrated guidance for FastAPI services — with the focus on what makes AI/ML/LLM serving different from an ordinary CRUD API. It is a knowledge skill: it teaches the decisions and the traps, then routes you to a per-topic reference for depth.

Stock agents already write basic FastAPI well (routes, Pydantic models, simple CRUD). This skill spends its tokens on the parts they get wrong by default: the concurrency model, the lifespan/singleton lifecycle, the security boundaries, and the discipline that turns a stochastic LLM into a typed component.

Inspired by FastAPI for AI Engineers: From First Endpoint to Production-Scale AI Systems (AI Engineering Insider, 2026). All content here is re-expressed in original wording; consult the book for its worked examples and case studies.

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