Spawn menu list/category

How would I create a spawnlist/spawn category on the Spawn(Q) menu?
As in, make a custom tab, and place items onto it?
I’ve looked everywhere, and this seems like a very un-documented thing, how would I go about doing this?
Could you provide any code to help out?

Thanks,
Safixk

What you want is the spawnmenu library.
If you need documentation, look through the source code.
(Also try to document stuff on the main wiki page (wiki.garrysmod.com), if you find stuff out)

Wonderful, thanks a bunch