Warning: this is a long one, mostly review! Skip to the end for the good stuff if you're in a hurry.
I've gone back and read a lot of the earlier questions, and the main problem is they were written when the site was much younger (the main "reference guide" is from 2011), and there were far fewer questions. I think it's worth revisiting how to apply those ideas to our current situation.
First, some source questions, newest to oldest:
If you go by those meta discussions, character tags have always been frowned on; obviously, that's not a policy that was strictly enforced, or we wouldn't have so many, but at least it has been consistently stated.
First off, the point of tags in general, as quoted from @Gilles' answer to the original Star Wars question:
Tags are useful for two things:
For people to subscribe to them or ignore them.
To classify questions in a manner that goes beyond plain text search.
He goes on to explain why character tags typically don't fit either of those two criteria:
For example a Star Wars fan would want to browse every question tagged star-wars, and a Star Wars hater would want to ignore these questions. But are you going to ignore questions tagged jar-jar just because you hate the character? If you're in love with Princess Leia, does that mean you specifically want to read all princess-leia questions and not other star-wars questions?
A question about R2-D2 would contain “R2-D2” or at least “R2D2”, so the tag isn't helping much.
In a comment to that same answer, @DavRob60 first mentions one criterion for determining if a character tag is a good tag:
when we will get more star-wars question, and a rather large subset of them on some specific character, the need of character specific Tags would arise.
@Jeff also seems to echo this sentiment in his own answer
I'm uncertain that there will be a great need for them - do these characters really have enough unique questions to warrant their own tags?
Both of these ideas pop up again in subsequent character tag questions, such as this answer (again from @Gilles) about voldemort:
A tag for a character is only warranted if there are a lot of questions about that particular universe (HP and ST do qualify), and a significant fraction of these questions are specifically about that character. If the tag is used on every question that mentions the character, that defeats the purpose.
Finally, as this topic has come up again recently, @phantom42 brings up another thing to factor in (again, initially related to Star Wars):
Given that there are entire solo books and comics dedicated to vader and obi-wan, I'm inclined to let those ones live. I think the amount of dedicated material should play into our culling
Which brings us to this question, and what our current guidelines should be. In trying to boil down all the past discussions to use as guidance for our cleanup efforts, I think we've settled on the following general rule for character tags:
A character-specific tag is only useful, and should only be created/kept, if there is enough material unique to that character, within their larger universe, to generate questions specifically about that character, such that one or more of the following is true:
- Users may want to follow/ignore just that character, but not the rest of the work.
- Someone may be an "expert" on just that character, and no other part of the work.
- The character appears in a significant amount of their own material
So far, some of the metrics we have been informally using, based on coordinating our efforts in chat, have been:
- A character that has their own spin-off titles automatically gets to stay.
- A character tag with few questions and no followers is an easy delete.
- A character that has lot of questions where they're the only character tagged in it, that tag will likely stay.
- A character tag with lots of people following it probably stays.
But that's obviously an incomplete list, so it can definitely use enhancement and refinement.
(on a side note: all the old meta discussions seem to agree that character tags are bad unless there's compelling proof otherwise. Assuming that's still the consensus, the criteria we come up with ought to be pretty hard to meet.)