How do you define the content that is tracked and displayed in all Incident record activity streams?
Use tags to filter the items that appear in the activity stream.
Tags enable you to filter your activities in the activity stream by dynamic and static states not offered in filter lists. For example, these states can include Workaround or Status checked.
https://www.servicenow.com/docs/bundle/yokohama-customer-service-management/page/product/customer-service-management/concept/config-csm-ws-activity-stream-tags.html