Agent engineering: Pydantic AI

This is the fifth take on the same news reader. The Claude Agent SDK version was a single Python file with tools and sub-agents. The Pi SDK version was a single TypeScript file with an event-based session. This time I used Pydantic AI, the agent framework from the Pydantic team.

Pydantic AI’s pitch is that since every AI library already depends on Pydantic for validation, you might as well build agents directly on it. The result feels like FastAPI for agents: decorators, type annotations, and automatic schema generation.