[Release] google/adk-python v1.27.0: v1.27.0

Google ADK Python v1.27.0 introduces major enhancements across core agent functionality, LLM model support, and observability. Key additions include A2A request interceptors, pluggable auth integrations, PDF support for Anthropic models, streaming capabilities, and new optimization tools. The release also expands tool ecosystems with Skills support, BigQuery enhancements, and improved human-in-the-loop interactions in the web interface.

Key Points

• •Introduce A2A request interceptors in RemoteA2aAgent for enhanced agent-to-agent communication control
• •Add pluggable AuthProviderRegistry in CredentialManager for flexible auth integration support
• •Support all types.SchemaUnion as output_schema in LLM Agent for broader schema compatibility
• •Add streaming support for Anthropic models and PDF document handling capabilities
• •Enable output schema with tools for LiteLLM models and preserve thought_signature in tool calls
• •Implement new `adk optimize` command with GEPA root agent prompt optimizer for agent performance tuning
• •Add UiWidget support in EventActions for experimental UI Widgets feature
• •Enhance observability with new OpenTelemetry semantic conventions and span attributes (gen_ai.agent.version, gen_ai.tool.definitions)
• •Expand Skills ecosystem with GCS filesystem support, BashTool, and ADK tools integration in SkillToolset
• •Improve human-in-the-loop with direct chat responses to long-running functions and artifact rendering on resume

Workflow Diagram

Concepts