heartbeat

Heartbeat example (v1.1)

Demonstrates ARCP v1.1's heartbeat feature: the runtime emits session.ping envelopes on a fixed cadence and the client replies with session.pong. The runtime declares its cadence in session.welcome.payload.heartbeat_interval_sec.

This server uses a 5-second interval (vs. the 30 s default) so the demo finishes in a handful of seconds.

Run

In one terminal:

pnpm tsx examples/heartbeat/server.ts

In a second terminal:

pnpm tsx examples/heartbeat/client.ts

The client connects, prints heartbeat_interval_sec=5, submits one echo job to prove the round-trip, then idles for ~12 s and prints the ping count. Two pings are expected.

What it demonstrates

• §6.4 session.ping / session.pong envelopes.
• §6.2 heartbeat_interval_sec advertisement on session.welcome.

Configuration

Env var	Default	Used by
ARCP_DEMO_PORT	7885	server
ARCP_DEMO_URL	ws://127.0.0.1:7885/arcp	client
ARCP_DEMO_TOKEN	demo-token	both