Pydantic AI AI Updates: October 16, 2026

1. Pydantic AI 2.57.0 Adds Meta Muse Provider and Model-Based Tool Approval

Pydantic AI. Pydantic AI 2.57.0 adds a MetaProvider for Meta Muse models, with the meta: prefix using the Responses API, and a Harness ApprovalReviewer that lets a model approve low-risk tool calls before a person sees them. The release also prices requests at their reported service tier, adds dataset_name to EvaluationReport, forwards MCP Apps tool results to AG-UI and Vercel AI frontends, and adds MCPToolset.read_resource_contents and MCPToolset.call_tool_for_app. Compatibility notes include Skills now honouring disable-model-invocation and user-invocable, and GPT-Live and Gemini Live realtime sessions taking history, usage, and reply waits from the session core. Bug fixes cover token-based compaction keeping too little recent history, durable DBOS sleeps between continuation polls, and SpendLimits charging the partial response of interrupted streams. Source