@agentplat/streaming

Server-Sent Events helpers for normalized AgentStreamEvent streams. The package depends on Web Standards and small structural Node response types; it does not depend on Next.js, Express or Hono.

Installation (developer preview)

Install the coordinated preview explicitly:

npm install @agentplat/streaming@next

Keep all @agentplat/* packages on the same release version. npm's default latest tag can point to an older preview. See the release channels for distribution status and version selection.

Next.js App Router

import { toNextSseResponse } from "@agentplat/streaming";

return toNextSseResponse(request, (signal) =>
  session.stream({ input: scenario, signal }),
);

Web Response (Hono and other Fetch-compatible frameworks)

import { streamToSSE } from "@agentplat/streaming";

return streamToSSE(runtime.stream(agent, input, context), {
  signal: request.signal,
});

Express-style response

import { pipeSSE } from "@agentplat/streaming";

await pipeSSE(runtime.stream(agent, input, context), response);

Browser parser

import type { MultiAgentSessionEvent } from "@agentplat/framework";
import { parseAgentSseStream } from "@agentplat/streaming";

for await (const envelope of parseAgentSseStream<MultiAgentSessionEvent>(
  response.body,
  { signal },
)) {
  // Envelope v1 is parsed and its sequence is validated.
}

The wire envelope is versioned and includes a monotonic sequence number. Do not send credentials or secrets in runtime stream event payloads.

For callback-style UI integration, use subscribeAgentSse(response, { onEvent, onError, signal }). It uses the same parser and rethrows malformed or failed streams after invoking onError.