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# subscribe

> Subscribe to a custom signaling event type on this call.

```ts
subscribe(eventType): Observable<Record<string, unknown>>
```

Subscribe to a custom signaling event type on this call.

Returns a cached observable that filters `callSessionEvents$` for events
whose `event_type` matches the given string. The observable completes
when the call is destroyed.

Unlike `signalingEvent$` (which only emits known call-level event types),
this method also matches custom/user-defined event types.

The SDK does not validate event type strings --- the server decides
whether a given type is valid.

## **Parameters**

**`eventType`** `string` — required

The event type to subscribe to (e.g. `'my.custom.event'`).

---

## **Returns**

`Observable<Record<string, unknown>>`

An observable that emits matching signaling events.

## **Examples**

```ts
call.subscribe('my.custom.event').subscribe(event => {
  console.log('Custom event:', event);
});
```

> Subscribe to a custom signaling event type on this call.