Pydantic v2

Overview

Pydantic v2 validates and serializes data from Python type hints. A BaseModel subclass declares fields as annotations; constructing it validates and coerces the input, and the instance round-trips to dicts/JSON via model_dump*. This skill is the knowledge delta for writing current v2 — the post-v1 API (model_config = ConfigDict(...), model_dump(), @field_validator) plus the pitfalls that bite when v1 muscle memory leaks in. It covers standalone Pydantic: models, fields, validators, serialization, config, pydantic-settings, TypeAdapter, and structured/union types. For framework-level request/response modeling and response_model, see the fastapi skill — this skill does not duplicate framework mechanics.

When to activate