> For a complete index of all SignalWire documentation pages, fetch https://signalwire.com/docs/llms.txt

# isSelfParticipant

> Type guard that checks if a participant is the local SelfParticipant.

```ts
isSelfParticipant(participant): participant is SelfParticipant
```

Type guard that checks if a participant is the local [SelfParticipant](/docs/browser-sdk/v4/reference/self-participant).

## **Parameters**

Participant to test.

## **Returns**

`participant is SelfParticipant`

## **Examples**

### Narrow at the type level

```ts
import { isSelfParticipant } from '@signalwire/js';

call.participants$.subscribe((participants) => {
  for (const p of participants) {
    if (isSelfParticipant(p)) {
      // p is typed as SelfParticipant here — local-only methods are available.
      p.startScreenShare?.();
    }
  }
});
```