pydantic/pydantic-ai v1.71.0 on GitHub

What's Changed

Add Capabilities: composable, reusable units of agent behavior that bundle tools, lifecycle hooks, instructions, and model settings into a single class you plug into any agent by @DouweM in #4640
Add AgentSpec and Agent.from_file for loading agents from YAML/JSON, with support for templated instructions referencing deps (via TemplateStr) by @DouweM in #4640
Add Hooks capability for defining hooks using decorators by @DouweM in #4640
Add Thinking capability and cross-provider thinking model setting by @DouweM in #4640
Add provider-adaptive tools capabilities WebSearch, WebFetch, MCP, ImageGeneration that automatically fall back from builtin (provider) tools to local tools by @DouweM in #4640
Add AbstractToolset.for_run and for_run_step for state isolation by @DouweM in #4640
Add openai:gpt-5.4-mini and openai:gpt-5.4-nano by @adtyavrdhn in #4787

Full Changelog: v1.70.0...v1.71.0