Pydantic AI Updates: May 15, 2026

1. Pydantic AI v1.96.1 deprecates more Agent constructor args and fixes OpenAI regressions

Pydantic AI. v1.96.1 continues the v2 staging by deprecating prepare_tools=, prepare_output_tools=, and event_stream_handler= on the Agent constructor in favor of the capability classes PrepareTools, PrepareOutputTools, and ProcessEventStream. It also patches two OpenAI integration bugs: the image-generation tool now omits input_fidelity when None rather than sending it as a literal, and the Responses model finally honors the openai_system_prompt_role setting instead of hardcoding the role. Source