if your log is collected thru OneAgent, it will set the target entity as the host/PG from where the log come, so the tag you have in that entity will be used by your alerting profile.
A property is a key/value pair that is set on every triggered event. You can have one or more placeholders as a value that will be extracted from the log data. For example, a property with Key set to PGI and a Value of placeholder {dt.entity.process_group_instance} will extract the process group instance value from log data once the event is triggered. If the placeholder substitution fails, both the key and the value will not be available.
I have a similar situation. I have log ingestion by the api. Fields im sending are content, log level, host.id, application. Customer wants a maintenance window for this event extraction that generate a problem card. So how do I setup the entity for this? I do not see an entity filed for Logs or host.id? Any ideas how to include this custom event extraction to not alert during off hours? How would I construct the entity selector to include this in my maintenance window?