I've seen many cases where the perspective of an image leaves the anus and/or vagina unseen or obscured, usually in cases where the person in the image is a Dickgirl/Herm. This usually causes a lot of conflict in the comments over whether it is Anal_penetration or Vaginal_Penetration, and again usually occurs in cases of Dickgirls/Herms.
The Ambiguous_penetration tag is used in these situations where one cannot specify which hole is being penetration, this is a very useful, albeit underused, tag that I hope to see more people being aware of in the future.

Qmannn said:
Characters with a penis and breasts are tagged dickgirl instead of herm if there's no proof/strong evidence of a vagina. Since, as far as e621's definitions are concerned, dickgirls don't have a vagina, the penetration would have to be anal.

The only time a herm would be getting this tag is if they were noted or shown to have a vagina somewhere in the image.

I am aware, I'm not saying anything about whether to tag as Dickgirl or Herm, I'm saying that in the event that you cannot see which hole something is going into, it's better to tag as Ambiguous_penetration rather that just guess. Example: https://e621.net/post/show/755610

Added forum to tag group:ambiguous tags

I doubt that I'll ever tag that myself, as long as there's more important things left to tag. Why search for ambiguous penetration, when you can just search for a specific type or simply for penetration (combined with whatever type you want to exclude)?

TheDarkInfinity said:
it's better to tag as Ambiguous_penetration rather that just guess. Example: https://e621.net/post/show/755610[/quote]
As Qmannn said, that doesn't look ambiguous. The character is tagged as a dickgirl, therefore shouldn't it be tagged as either anal_penetration or just penetration?