# observationOpen

`import { observationOpen } from "destack:runtime";`

Open one runtime observation subscription.

```ds title="observationOpen"
export declare function observationOpen(world: WorldHandle, options?: ObservationOptions | undefined): Result<ObservationHandle, HostError>
```

[language/library/src/runtime/observation.ds:70:73](https://github.com/destack-sh/destack/blob/main/language/library/src/runtime/observation.ds#L70-L73)