Currently when retrieve activity logs for a ticket from REST web service GET method, all activity logs return,including the internal logs. This tech doc provides the way to exclude the internal logs.
In the GET endpoint, "and%20internal%3D0" would need to be added to the end of the URL to exclude the internal logs.
For example, for call request/incident/problem tickets, the endpoint will look like
where cr:xxxxxx is the persid of the ticket.
For change order tickets, it will look like
where xxxxxx is the id of the change order ticket.
And for issue tickets, it will look like
where xxxxxx is the issue id.