pydantic-ai 2.12.0

v2.12.0 (2026-07-16)

on Python PyPI

What's Changed

🚀 Features

• Add Moonshot AI kimi-k3 model by @dsfaccini in #6551
• Emit EnqueuedMessagesEvent when enqueued messages are delivered into the run by @DouweM in #6256
• feat: add DeferredToolCallEvent and DeferredToolResultEvent to AgentStreamEvent by @YHallouard in #5588

🐛 Bug Fixes

• Fix ToolReturnPart serialization to use field aliases so wire output matches return_schema by @pydanty[bot] in #6543
• Fix tool binding for POSITIONAL_OR_KEYWORD params with *args by @pydanty[bot] in #6541
• fix(mistral): defer streamed output emission when text ends mid-integer-token by @Mukller in #6519
• Derive capability-contributed toolset id from the capability for durable execution by @dsfaccini in #6408
• Fix GoogleModel per-Part media_resolution forwarding in vendor_metadata by @pydanty[bot] in #6525

New Contributors

• @Mukller made their first contribution in #6519
• @YHallouard made their first contribution in #5588

Full Changelog: v2.11.0...v2.12.0