Pydantic AI Updates: October 20, 2026

1. Pydantic AI 2.58.0 and 1.107.8 Patch Two Medium-Severity Advisories Affecting MCP and UI Adapters

Pydantic AI. Pydantic AI released v2.58.0 and v1.107.8 on October 19 to fix GHSA-xv4x-g8mx-ch56, under which provider-native MCP configuration could write MCP server URLs, authorization tokens, and custom header values into OpenTelemetry traces even with include_content=False; the maintainers advise restricting access to historical traces and rotating exposed credentials. A second advisory, GHSA-5pfm-2g3g-gh85 (v2 only), let the Vercel AI and AG-UI UI adapters execute an available tool with client-chosen arguments and no model request when server-side message_history was non-empty and manage_system_prompt='server' (the default); tools requiring approval were not reachable. Teams exposing agents to browser frontends through these adapters should upgrade, and Temporal users should pass an explicit id= to MCP once in-flight workflows complete. Source

Pydantic AI. The release adds timeout= and RunContext.deadline to bound a whole agent run, plus ModelSettings['request_timeout'] and ModelSettings['max_retries']; models that ignore such settings now emit an UnsupportedSettingWarning instead of silently dropping them. A new openai-chatgpt provider lets app users sign in with ChatGPT and use their own plan, ElevenLabsAgentsRealtimeModel runs realtime sessions on ElevenLabs Agents, and DelegationTasks.steer redirects a running delegated task. Existing DBOS workflows that use Planning with an event_stream_handler may not recover after upgrading, so the maintainers recommend letting in-flight workflows finish or deploying a new DBOS application version first. Source

1. Pydantic AI 2.58.0 and 1.107.8 Patch Two Medium-Severity Advisories Affecting MCP and UI Adapters

2. v2.58.0 Adds Run-Level Timeouts, a ChatGPT Sign-In Provider, and an ElevenLabs Realtime Model