A note on the Metadata property
Elastic Cloud Serverless projects are autoscaled environments, fully managed by Elastic and available on Elastic Cloud. Availability This functionality is generally available and ready for production usage. Serverless interfaces and procedures might differ from classic Elastic Stack deployments. The Elastic Stack includes Elastic's core products such as Elasticsearch, Kibana, Logstash, and Beats. Availability This functionality is generally available and ready for production usage. Unless stated otherwise on the page, this functionality is available when your Elastic Stack is deployed on Elastic Cloud Hosted, Elastic Cloud Enterprise, Elastic Cloud on Kubernetes, and self-managed environments. This documentation corresponds to the latest patch available for each minor version. If you're not using the latest patch, check the release notes for changes.
Serverless
Generally available
Stack
Generally available
The C# EcsDocument type includes a property called Metadata with the signature:
/// <summary>
/// Container for additional metadata against this event.
/// </summary>
[JsonPropertyName("metadata"), DataMember(Name = "metadata")]
public IDictionary<string, object> Metadata { get; set; }
This property is not part of the ECS specification, but is included as a means to index supplementary information.