a2a/
├── infra/
│   ├── main.tf              # App registration, roles, assignments
│   ├── variables.tf          # UPNs, redirect URIs
│   └── outputs.tf            # Client ID, secret, tenant ID
├── src/
│   ├── agents/
│   │   ├── wiki/             # Wikipedia agent + card
│   │   ├── duck/             # DuckDuckGo agent + card
│   │   └── text_agent/       # Data agent with row-level access
│   ├── client/
│   │   ├── common.py         # Shared A2A tool factory
│   │   ├── orchestrator_agent/  # CLI orchestrator
│   │   └── streamlit_app/    # Streamlit UI + auth
│   ├── a2a_server/
│   │   ├── base.py           # Starlette server + routing
│   │   ├── auth.py           # JWT validation + middleware
│   │   ├── text_executor.py  # LangChain ↔ A2A bridge
│   │   └── types.py          # Streaming event types
│   └── util/
│       ├── settings.py       # Pydantic settings from .env
│       └── config.py         # LLM configuration
└── pyproject.toml            # uv project with entry points