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# Availability

> Mark features as available in specific SDK versions using `x-fern-availability` extension

Mark features as available in specific SDK versions:

```yaml title="asyncapi.yml" {6-8}
operations:
  newFeature:
    action: send
    channel:
      $ref: '#/channels/new~1feature'
    x-fern-availability:
      status: beta
      message: "This feature is in beta and may change"
```