A2A Multi-Agent Development

Build multi-tier ADK agent systems using the A2A protocol, deployed to Agent Engine.

Architecture Pattern

Level 1: Orchestrator (routes requests)
├── Level 2: Functional Agent A (delegates to leaf)
│   └── Level 3: Leaf Agent A (has tools, does work)
└── Level 2: Functional Agent B (delegates to leaf)
    └── Level 3: Leaf Agent B (has tools, does work)

Key principle: Leaf agents have tools. Functional agents delegate. Orchestrators route.

Quick Reference