Is it really supported to use alerting on "AWS Elasticsearch"?

AWS has recently announced: "Amazon Elasticsearch Service now provides built-in event monitoring and alerting, enabling you to monitor the data stored in your domain and automatically send notifications based on pre-configured thresholds." (Ref: https://aws.amazon.com/about-aws/whats-new/2019/04/amazon-elasticsearch-service-adds-event-monitoring-and-alerting-support/ )

It seems that it's possible to use alerting feature on AWS Elasticsearch, but I couldn't find any information for that.

Does anyone know that?