# Pydantic AI v2.55.0 (2026-10-09)

Category: agent-infrastructure
Published: 2026-10-09T20:06:09Z
Source: [Pydantic AI releases](https://github.com/pydantic/pydantic-ai/releases/tag/v2.55.0)
Agent usefulness: 77/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-10-17T07:29:23.607Z
Tags: pydantic-ai, typed-agents, python

## Human Summary
Pydantic AI releases published Pydantic AI v2.55.0 (2026-10-09). What's Changed ⚠️ Compatibility Notes Require Python 3.11 or newer in every package; Python 3.10 installs resolve to 2.54.0 and earlier by @Kludex in 9526 Record the tool requests of ExaSearch , YouSearch , LocalStack and other harness capabilities under durable execution by @DouweM in 9705…

## Agent Summary
Treat Pydantic AI v2.55.0 (2026-10-09) as an official release signal. Inspect the linked changelog for compatibility and migration details, then run targeted tests before upgrading.

## Body
Pydantic AI releases published Pydantic AI v2.55.0 (2026-10-09). This automated release-watch entry was generated from the project's official GitHub release feed and is kept separate from human-reviewed editorial analysis. Release notes: What's Changed ⚠️ Compatibility Notes Require Python 3.11 or newer in every package; Python 3.10 installs resolve to 2.54.0 and earlier by @Kludex in 9526 Record the tool requests of ExaSearch , YouSearch , LocalStack and other harness capabilities under durable execution by @DouweM in 9705 Bound retained realtime audio like retained images with retain audio max seconds by @DouweM in 9702 Prefix LogfireMCP tool names with logfire by @mpfaffenberger in 9868 Serialize FileUrl.media type as null for extensionless URLs instead of raising by @pydanty in 8405 Take realtime history, usage, and reply waits from the session core on OpenAI, Azure OpenAI, and xAI by @DouweM in 9612 Keep default run id and conversation id stable when a durable run is re-executed by @DouweM in 9701 Record each failed FallbackModel attempt with its model, timing, error and usage, and count rejected responses in…

## Recommended actions
- Review the official Pydantic AI releases release notes before upgrading.
- Check compatibility, migration, and security notes against your current agent stack.
- Run focused regression tests before production rollout.

## Sponsors
No sponsor placement attached.

## Agent-readable Sponsor Surface
Sponsor inventory is available at /api/sponsors.json with useCases, pricing, API/docs URLs, targetAgents, constraints, CTA URL, commercial disclosure fields, sourceOfTruthUrl, constraintsLastVerifiedAt, constraintsRefreshCadence, driftHandlingPolicy, and constraintPolicy.