2.55.0

New Features ✨

Anthropic

• Record finish reasons in AI monitoring spans by @ericapisani in #5678
• Emit gen_ai.chat spans for asynchronous messages.stream() by @alexander-alderman-webb in #5572
• Emit AI Client Spans for synchronous messages.stream() by @alexander-alderman-webb in #5565
• Set gen_ai.response.id span attribute by @ericapisani in #5662
• Add gen_ai.system attribute to spans by @ericapisani in #5661

Pydantic Ai

• Support ImageUrl content type in span instrumentation by @ericapisani in #5629
• Add tool description to execute_tool spans by @ericapisani in #5596

Other

• (crons) Add owner field to MonitorConfig by @julwhitney13 in #5610
• (otlp) Add collector_url option to OTLPIntegration by @sl0thentr0py in #5603

Bug Fixes 🐛

• (ai) Truncate list-based message content in AI monitoring by @ericapisani in #5631
• (anthropic) Close span on GeneratorExit by @alexander-alderman-webb in #5643
• (celery) Propagate user-set headers by @sentrivana in #5581
• (langchain) Wrap finish_reason in array for gen_ai span attribute by @ericapisani in #5666
• (logging) Fix deadlock in log batcher by @sentrivana in #5684
• (profiler) Prevent buffer race condition during rapid start/stop cycles by @ericapisani in #5622
• (utils) Avoid double serialization of strings in safe_serialize by @ericapisani in #5587
• Enable unused import ruff check and fix unused imports by @sentrivana in #5652

Documentation 📚

• (openai-agents) Remove inapplicable comment by @alexander-alderman-webb in #5495
• Add AGENTS.md by @sentrivana in #5579
• Add set_attribute example to changelog by @sentrivana in #5578

Internal Changes 🔧

Anthropic

• Check system and response ID attributes on spans created by stream() by @alexander-alderman-webb in #5665
• Skip accumulation logic for unexpected types in streamed response by @alexander-alderman-webb in #5564
• Factor out streamed result handling by @alexander-alderman-webb in #5563
• Stream valid JSON by @alexander-alderman-webb in #5641
• Stop mocking response iterator by @alexander-alderman-webb in #5573

Openai Agents

• Do not fail on new tool fields by @alexander-alderman-webb in #5625
• Stop expecting a specific function name by @alexander-alderman-webb in #5623
• Set streaming header when library uses with_streaming_response() by @alexander-alderman-webb in #5583
• Replace mocks with httpx for streamed responses by @alexander-alderman-webb in #5580
• Replace mocks with httpx in non-MCP tool tests by @alexander-alderman-webb in #5602
• Replace mocks with httpx in MCP tool tests by @alexander-alderman-webb in #5605
• Replace mocks with httpx in handoff tests by @alexander-alderman-webb in #5604
• Replace mocks with httpx in API error test by @alexander-alderman-webb in #5601
• Replace mocks with httpx in non-error single-response tests by @alexander-alderman-webb in #5600
• Remove test for unreachable state by @alexander-alderman-webb in #5584
• Expect namespace tool field for new openai versions by @alexander-alderman-webb in #5599

Other

• (graphene) Simplify span creation by @sentrivana in #5648
• (httpx) Resolve type checking failures by @alexander-alderman-webb in #5626
• (pyramid) Support alpha suffixes in version parsing by @alexander-alderman-webb in #5618
• (rust) Don't implement separate scope management by @sentrivana in #5639
• (strawberry) Simplify span creation by @sentrivana in #5647
• 🤖 Update test matrix with new releases (03/16) by @github-actions in #5671
• Remove custom warden action by @sentrivana in #5653
• Add httpx to linting requirements by @alexander-alderman-webb in #5644
• Remove CodeQL action by @sentrivana in #5616
• Normalize dots in package names in populate_tox.py by @alexander-alderman-webb in #5574
• Do not run actions on potel-base by @sentrivana in #5614