pydantic-models-py

name	pydantic-models-py
description	Pydantic v2 multi-model pattern for clean API contracts — Base, Create, Update, Response variants with camelCase aliases and PATCH support. Use when defining FastAPI request/response schemas or data validation models.
allowed-tools	Read, Write, Edit
metadata	{"triggers":"Pydantic models, API schema, request body, response model, Pydantic BaseModel, data validation, PATCH endpoint, camelCase alias, API contract, request/response schema","related-skills":"python-dev, openapi-spec-generation, api-design-principles","domain":"backend","role":"specialist","scope":"implementation","output-format":"code"}
last-reviewed	2026-03-14

Iron Law

NEVER USE A SINGLE PYDANTIC MODEL FOR BOTH CREATE AND RESPONSE — separate contracts prevent leaking internal fields, block over-posting, and make API evolution safe

Pydantic v2 Models

Create Pydantic models following the multi-model pattern for clean, safe API contracts.

Multi-Model Pattern

Model	Purpose	Required Fields
Base	Common fields shared across all variants