Google ADK for Java 1.0 Introduces New App and Plugin Architecture, External Tools Support, and More

Google's Agent Development Kit (ADK) for Java has reached version 1.0, bringing several major additions. New external tool integrations include GoogleMapsTool, UrlContextTool, ContainerCodeExecutor, VertexAICodeExecutor, and ComputerUseTool (with Playwright). The release introduces an App and Plugin architecture with built-in plugins for logging, context filtering, and global instructions. Event compaction is now supported to manage context window size in long-running sessions. Human-in-the-loop workflows allow agents to pause, request approval, and resume execution. Native support for the Agent2Agent (A2A) protocol enables cross-language and cross-framework agent collaboration. Community discussion notes concerns about Google's Java library maintenance track record, while others highlight Java's type safety as an advantage for agent stability at scale.