@weaveintel/a2a

Let your agents talk to other agents over the Agent-to-Agent (A2A) protocol — as a client, a server, or both.

Why it exists

One agent rarely knows everything. Sometimes the right move is to delegate: hand a task to a specialist agent that lives somewhere else and wait for it to report back. A2A is the shared etiquette for that hand-off — like two colleagues agreeing on how to send a work request, check on its progress, and get notified when it's done. This package speaks that etiquette on both sides: it can hire other agents, and it can turn one of your own agents into a hireable service.

When to reach for it

Reach for it when agents in different processes or services need to delegate tasks to each other. If you just want your agent to call plain tools (not other agents), you don't need this — use a ToolRegistry from @weaveintel/core. For a single in-process test you can skip HTTP entirely with weaveA2ABus.

How to use it

import { weaveA2AClient } from '@weaveintel/a2a';
import { weaveContext } from '@weaveintel/core';

const client = weaveA2AClient();
const ctx = weaveContext();

const card = await client.discover('https://agents.example.com/research');
const agentUrl = card.supportedInterfaces?.[0]?.url ?? card.url!;

const task = await client.sendMessage(ctx, agentUrl, {
  message: { role: 'user', parts: [{ text: 'Summarize Q3 sales' }], messageId: 'm1', contextId: 'c1' },
});

console.log(task.status.state);   // e.g. "TASK_STATE_COMPLETED"

What's in the box

| Export | What it does | | --- | --- | | weaveA2AClient() | Client: discover, sendMessage, streamMessage, getTask | | weaveAgentAsA2AServer(opts) | Turn one of your agents into an A2A-serving endpoint | | weaveA2ABus() | In-process client↔server bus (no HTTP) for tests/embedding | | createA2ADispatcher, weaveA2AServer, streamToSse | JSON-RPC 2.0 server dispatch + SSE streaming | | create*A2ATaskStore / createSqliteA2ATaskStore | In-memory, durable, or SQLite task persistence | | signAgentCard, verifyAgentCard, createJwtValidator | Card signing and JWT auth for trusted agents | | createInMemoryPushNotificationStore, deliverToWebhook | Webhook push notifications for task updates |

License

MIT.