Due to newcomers and familiar users alike reverting, adding, or otherwise making a mess of these tags I will now post this here with the hopes it gets stickied.

The gender is tagged per image, by the e621.net tagging guidelines: Tag What You See, Not What You Know. To be identified, primary sexual characteristics (penis, pussy, breasts, etc) must be visible, if none are, and you can't clearly identify the gender, tag as ambiguous_gender.

Comics follow the TWYSNWYK rule and are judged on an image to image basis.

Tags are as follows:

Visible penis + no visible female genitalia at all = male

visible penis + visible breasts - visible pussy = dickgirl
Not having testicles (balls) does not affect this tag. Chakats with no visible pussy do not affect the tag.

Visible penis + visible pussy = herm
Not having testicles (balls) does not affect this tag.

Visible pussy + visible breasts - visible penis = female

Visible pussy - visible breasts - visible penis = cuntboy

Not trying to usurp the admins' jobs or anything, I am just tired of fighting/reporting/reverting tags on a day to day basis with users who think the TWYS rule doesn't apply to them or the image in question.

There is gender tagging flowchart on forum #39607
Maybe it should be made sticky. (If it's correct.)