The event types to subscribe to. Omit this field to receive everything — it defaults to [""]. Passing [""], on its own or alongside specific types, has the same effect. Otherwise only events matching the values you pass are delivered. Matching is a wildcard pattern match, so a category wildcard such as "transfer.*" subscribes you to every event in that category. Each value must be one of the available notification types. This list cannot be changed after the subscription is created — create a new subscription instead.