pi-mono/packages/client

@earendil-works/pi-client

Transport-neutral client for remote pi sessions. PiClient exchanges length-prefixed CBOR messages through a small ByteTransport interface. The package has no Node-specific imports.

import { PiClient, type ByteTransportFactory } from "@earendil-works/pi-client";

const transportFactory: ByteTransportFactory = async (handlers) => {
  // Connect using WebSocket, Unix socket, or another ordered byte transport.
  return {
    async send(chunk) {
      // Deliver chunks in invocation order and honor backpressure.
    },
    close() {},
  };
};

const client = new PiClient({ token: bearerToken, transportFactory });
await client.connect();
const session = await client.createSession({ cwd: "/workspace" });
const unsubscribe = session.subscribe((snapshot) => render(snapshot));
await session.prompt("Inspect this project");
unsubscribe();

Call handlers.onData(chunk) for inbound bytes, handlers.onClose() for an orderly terminal close, and handlers.onError(error) for transport failures. A factory must create a fresh transport for every connection attempt.

PiClient does not reconnect automatically. Call reconnect() after disconnection. One connection can attach several PiSessionClient handles. Requests are correlated by ID. Server snapshots and successful response snapshots are authoritative, while progress events do not mutate snapshot state optimistically.

subscribe() observes authoritative snapshots. onEvent() observes protocol events. Both return an unsubscribe function. A detached session handle remains readable, but commands throw PiSessionDetachedError until it is attached again.

Limits and security

PiClientOptions.maxFrameLength bounds inbound and outbound CBOR payloads. Configure matching limits on the client and server. Transports should separately bound queued outbound bytes and preserve send order.

Treat peers as untrusted. Use a secure transport where required and protect the protocol bearer token.