Currently garry's_mod implicates 3d_(artwork), but there are some posts that reference the game and are obviously not 3d. It is impossible to search for non 3d Garry's Mod art. At the very least, this should be unimplicated. Team_fortress_2 is in a similar situation, being a game that is frequently used for 3d artwork, but it doesn't implicate 3d_(artwork).

When I brought it up in the discord it was suggested twice that the the tag be split between something like garry's_mod(game) and garry's_mod(software). The former being for artwork referencing Garry's Mod and the latter for art created in Garry's Mod.

Whatever solution is used it should be easy to manually apply since there are only 300 posts, and very few are actually non 3d.

garry's_mod_(game) garry's_mod_(medium) makes more sense to me. The game is itself software, but not all Gmod images use Gmod as a medium.
We might also make this change for Source Filmmaker if there's non-SFM art making fun of its apparent quirks.

lafcadio said:
garry's_mod_(game) garry's_mod_(medium) makes more sense to me. The game is itself software, but not all Gmod images use Gmod as a medium.

Although we shouldn't be tagging software that's used to make images or videos. We don't tag photoshop or gimp (software) on images made in Photoshop or GIMP, only where the software itself is visible (its UI or logo or some other component). Source FilmMaker is supposed to only be for posts where you can see Source FilmMaker itself too, and the same goes for Blender (software), even though people keep tagging them wrong. So Garry's Mod should only be used on images where you can see something about Garry's Mod itself, not simply images or videos made with it. Even then, Garry's Mod is really just a way for people to create animations in the Source Engine. As it's name suggests, it started as a mod that people could animate cutscenes, which could be recorded to a video, but it was the Source Engine that actually played and rendered the animation.