Google Agent Development Kit (ADK) overview

Google's open-source framework for building, evaluating, and deploying AI agents. Provides a code-first approach with composable agent architectures — sequential agents, parallel agents, and loop agents for multi-step reasoning. Features built-in support for Google's Gemini models, tool calling with automatic schema generation, session state management, memory services, and artifact handling. Includes a local development UI for testing and debugging agent interactions. Natively supports the A2A (Agent-to-Agent) protocol for inter-agent communication and MCP tool servers for external tool integration. Deployable to Google Cloud (Vertex AI, Cloud Run) or any container environment.