Microsoft 365 Agents SDK for Python - Release Notes v0.9.0

Microsoft 365 Agents SDK for Python - Release Notes v0.9.0

Release Date: April 15, 2026
Previous Version: 0.8.0 (Released February 23, 2026)

Major Features & Enhancements

• OpenTelemetry Support: Full distributed tracing and metrics support with traces spanning adapter, app, auth, OAuth, storage, and turn-context layers. Includes a new OTel sample and comprehensive test coverage (#341)
• Proactive Messaging: New proactive module in AgentApplication with Conversation, ConversationBuilder, and ConversationReferenceBuilder abstractions for initiating outbound conversations (#350)
• FederatedCredentials Auth Type: Support for Managed Identity with Federated Identity Credential (FIC) authentication type in MSAL auth (#353)
• PFX Certificate Auth: Support for PFX files in MSAL Certificate authentication type (#349)

Bug Fixes

• MCS Connector: Fixed incorrect connector creation in RestChannelServiceClientFactory for MCS channels (#360)
• FastAPI JWT Middleware: Fixed parity with aiohttp by correcting async handling in JWT authorization middleware (#343)
• OpenTelemetry Testing Utility: Fixed DeltaMetricReader test utility (#362)

Developer Experience

• Streaming Consolidation: Moved StreamingResponse, Citation, and CitationUtil from hosting-aiohttp and hosting-fastapi into hosting-core, eliminating duplication (#339)
• PyJWKClient Caching: Added thread-safe JWK client caching with a dedicated JwkClientManager class to reduce redundant token-key fetches (#338)
• Connector Validation: Improved response-data validation in ConversationsOperations methods with added test coverage (#317)

Documentation

• Packages Overview: Added missing microsoft-agents-hosting-fastapi entry to the README packages overview (#346)