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A2A Protocol

Overview

Connect to any A2A v1.0 protocol-compliant agent server.

@assistant-ui/react-a2a is a runtime adapter for the A2A (Agent-to-Agent) v1.0 protocol. Use it when your backend speaks A2A; the adapter handles the wire protocol so you can focus on the UI.

When to use it

Pick the A2A runtime when:

  • You have an A2A v1.0 compatible agent server, or you are building one and want a reference client.
  • You want streaming task state, artifacts, and the protocol's full state machine surfaced in the UI.
  • You need multi-tenant or extension-aware A2A clients.

If your backend is not A2A-compliant, see picking a runtime for alternatives.

Architecture

@assistant-ui/react-a2a is layered on ExternalStoreRuntime (see architecture). Features that ship as runtime adapters (attachments, speech, feedback, history, threads) work the same way they do everywhere else; see adapters.

Requirements

  • An A2A v1.0 compatible agent server.
  • React 18 or 19.

Install

npm install @assistant-ui/react @assistant-ui/react-a2a

Next

QuickstartMinimal runtime setup with a Thread component.Client and hooksA2AClient, useA2ARuntime options, hooks reference, task states, artifacts.