Math Assistant A2A Example

Why it matters

The example runs MCP and A2A side by side in one agent, so the boundary between a tool and a remote agent stops being abstract. It also shows why remote agent access is scoped to a user.

What to practise

Expose the calculator workflow as an A2A server with nat a2a serve, then read its agent card with nat a2a client discover. Run the client workflow, a per_user_react_agent whose tool_names mix the calculator_a2a client, an MCP time tool and local logic functions. Under nat serve, send requests as two users — the nat-session cookie tells them apart — and watch that each user gets an isolated A2A connection while the MCP and local tools stay shared.

How it fits

Use the tool composition to test 1.3.1’s split between MCP for tools and A2A for agents. The discovery step is 1.3.2’s agent card in practice. The per-user client is where 1.3.3’s authentication attaches; the README defers OAuth2 to its protected variant.