Step 3 of 5

WebSocket subscription

Define the subscription handshake, the message templates and the connection tuning that Crank should use before collecting bounded WebSocket events.

Connection

The upstream base URL from step 2 becomes the WebSocket endpoint unless you override it here.

Optional

Socket path

Appended to the upstream URL from step 2. Leave empty if the upstream URL already points to the full WebSocket endpoint.

Subprotocols

One subprotocol per line. Crank offers them during the handshake in the same order.

Subscription messages

Templates are sent after the socket opens. They can reference MCP input through the mapping step.

Optional

Subscribe template

Unsubscribe template

Connection tuning

Used by the runtime adapter for heartbeats and reconnects in bounded session-oriented flows.

Optional

Heartbeat interval (ms)

Reconnect attempts

Reconnect backoff (ms)