heartbeat( )

function heartbeat(params?: { delegate?: DelegateBase }): Promise<HeartbeatResponse>;

Sends a heartbeat round-trip to verify that a delegated provider is online or that the local SDK worker is responsive. When called without arguments, checks the local worker.

Parameters

Name	Type	Required?	Description
params	`object`	✗	Optional delegation target
params.delegate	`DelegateBase`	✗	The provider to check — omit to check the local worker

`DelegateBase`

Consumers connect directly to the provider via the DHT using providerPublicKey — no topic or discovery step is required.

Field	Type	Required?	Description
providerPublicKey	`string`	✓	Provider peer public key hex string (from `startQVACProvider`)
timeout	`number`	✗	Connection timeout in milliseconds (min 100). On a cold DHT the first connect can take 15–45s.
healthCheckTimeout	`number`	✗	Health check timeout in milliseconds (min 100)

Returns

Promise<HeartbeatResponse>

`HeartbeatResponse`

Field	Type	Description
type	`"heartbeat"`	Response type discriminator
number	`number`	Round-trip sequence number

Throws

Error	When
`INVALID_RESPONSE_TYPE`	Response type does not match expected `"heartbeat"`

Examples

// Check if a delegated provider is online
try {
  await heartbeat({
    delegate: { providerPublicKey: "peerHex", timeout: 3000 },
  });
  console.log("Provider is online");
} catch {
  console.log("Provider is offline");
}

// Check if the local SDK worker is responsive
await heartbeat();