Sharpening is an identifiable task that's fundamental to many A&C processes, and people have questions specifically about that. I don't know if we've actively avoided giving it a tag, but we have 17 questions about sharpening, and many of them torture other tags in order to have some kind of tag.
For example, if I have a question about how to sharpen my pencil, I'm looking for tags that involve pencil and sharpening. If I'm searching for an answer, I'm searching on those tags. Nobody would think to use pencil-maintenance, even though that might be technically correct. And sharpening a leather punch is not tool-modification.
We might be able to pigeon-hole sharpening under some broader category, and that might be useful for a Wikipedia article on the taxonomy. But nobody thinks in those terms, so the current tag applications are pretty useless for tagging purposes.
Objective & Discussion
In A&C, there are two (that I can think of), meanings of "sharpen":
- putting a point or edge on an object
- making artwork detail visually distinct
The first bullet applies to pencils and other stick media, and to tools. If we had tons of questions about both, the clean approach would be to create two tags, like sharpen-media and sharpen-tools.
A tag that acts as a modifier for multiple subject tags is referred to as a "meta tag" and it isn't best practice. But it's also not useful for tagging purposes to have tags that apply to only a couple of questions. That can't be helped when your building out the site and need tags, and the site doesn't have many questions. In our case, combinations like sharpen+pencils or sharpen+tool is a good solution (tool isn't an actual current tag).
One could question whether we need a tag for the second meaning. We don't have tags for every kind of modification that can be done to artwork. And I would normally make that point if there was no other meaning of "sharpen" and the tag would apply only to the second meaning.
It is not inappropriate to have a tag for this. If we had tons of questions about modifying artwork, it might make sense to differentiate some of the different ways if that would help people find the relevant information.
So it comes down more to whether we need it and whether it would actually serve a useful purpose. I spotted one existing question where this might be an applicable tag (What is the way to color tiny parts of a picture with oil pastels?). We've also had some questions about creating detail, like drawing hair, where the OP or searchers might think of it in terms of sharpening (the tags are about the question and how the person is framing it or thinking about it, not the answer).
I don't know if we strictly need it, but it wouldn't harm anything to have it. The concept of sharpening is one of the fundamental actions in artwork, and people do have questions specifically about that.
Probably a bigger consideration is the existence of a closely-related tag. If we have a tag for the other meaning, people will misuse that for this meaning, or will create a tag (which won't necessarily be the best tag from a big picture perspective). It's preferable to just create a good tag and define it.
Two possible approaches come to mind.
We create a tag for each meaning. They should use terms that differentiate the meaning, and the terms should be what people normally think of.
Note that when you start to type a tag, the system suggests existing tags that contain the typed text. So one solution might be something along the lines of sharpen-objects and sharpen-artwork (these are just to illustrate the point, those probably aren't the best word choices). Typing the intuitive sharpen would display both, and the person could select the applicable one (and see the usage guidance when hovering).
If we think we will never need or want a tag for the second meaning, an alternate approach would be just a sharpen tag, and it would be defined as covering only the first meaning, with guidance not to use it for the second meaning. Since nobody reads the tag guidance, this approach will entail periodically editing the tag out of a question where it's inappropriate, and the tag guidance would be mainly for the curator.
Ideas or suggestions?