This task refers only to tags applied via API/scripts (as contrary to manually editing them by means of interface elements such as the Edit tags of selected revisions button on history pages). Steps taken on test.wikipedia.org:
- Edit some page through the API specifying a tags parameter with any existing tag (Applied manually...), let's say description. I used Special:ApiSandbox to perform an edit on this page with the mentioned tag.
- Go to Special:RecentChanges and check that your edit doesn't show as tagged. You can see there both of my untagged edits on 24th May. The filtered view doesn't show them either.
- Go to the history view of the edited page. The revision should be correctly tagged there (my test page), as well as in your contribs page. The corresponding Tagged changes counter on Special:Tags has been incremented, too.
I have first spotted this issue on pl.wiktionary.org. The last registered tagged edits with the only tag available for manual/per script applying (named Skrypt) occured on early 23th May (CET zone), although actually those weren't the last revisions to be tagged as it can be seen in this contribs list.