Problem Definition:

Currently when Configuring service desk notifications Depending on the chosen "When" Trigger event Option Selected Different Choose recipients options become available for the To option when sending an email, BUT there is no mention of which is available under each option only noting:

Choose recipients
Add at least one of the following to the To field:

Recipient options	Details
Reporter (customer)	The reporter of the request. This notification is sent even if the reporter has opted out of receiving notifications on the customer portal.
Customers involved	All customers involved on the request, including the reporter and request participants. This notification is not sent to customers if they have turned off notifications for an individual request in the portal or a request's email thread.
Added participants	The people who have been added as request participants. Added organizations The people in an organization that the request has been shared with.
Approvers	The people who need to approve or decline a request.
Exclude person who caused the action	Prevents the person who triggered the rule from receiving a notification. For example, if a customer adds a comment to a request, you can choose to exclude them so they don't receive a notification about their own comment.

As an EXE:
If you Choose: "WHEN=Status Changed" for the THEN Send Email "TO" Field only has the options "Reporter (Customer)" & "Customers Involved" available

Suggested Solution

Add information to available Choose recipients options per Trigger event

Current Options:

Additional Note:

There is also a limitation for the recipients to which an email can be sent by the "Send Email" action in the automation rules. We should specify it in the documentation Automating your Service Desk