PydanticAI
Type-safe Python agent framework with FastAPI-style developer ergonomics
View on GitHubWhat it solves
Type safety in agent development: catching schema mismatches and malformed tool calls at development time instead of debugging silent failures in production.
Overview
From the team behind Pydantic and FastAPI, PydanticAI brings the same type-first, dependency-injection design to agent development. Agents are typed Python classes; tool inputs and outputs are validated Pydantic models; the API surface mirrors FastAPI route decorators so Python developers feel at home immediately. Reached v1.0 API stability in September 2025.
Key facts
- Language
- Python
- License
- MIT
- Maturity
- Stable
- Maintainer
- pydantic
- Reviewed
- 2026-06-11
Where to start
The agents doc explains the System Prompt → Tool → Result Validator chain that PydanticAI enforces, the type annotations do most of the work.
docs/agents.mdTechnologies
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