As in, if I start a server with wiremod and a person does not have wiremod, what would he download? The luas? The models? What? I am afraid of my bandwidth going through the roof (hosting at home). Thank you.
Just the lua and map are sent unless you tell it differently.
Only LUA are downloaded if you talk about Wire / PHX, however, with certain addons, like Mario hat V2, the model will be also sent, because it’s a small file. And the author put a code in the autorun LUA.
You can force the client to download the whole materials/models of Wire and PHX, but I doubt he will be happy.