How to filter tagged elements to prevent duplicate tagging

I have a workflow to tag slope pipe. When i use it multiple times it duplicates the tag. Is there a way to filter out the tagged pipe, so im only tagging pipes that have yet to be tagged. There is a steam node “element is tagged” but im not quite sure how to use it. Any comments will be appreciated.

Thank you,


Try this:

Grab all tags, get their hosts, filter those from your selection set for new tags (assuming you are tagging all of a category visible in view).