As mentioned on the wiki to add folders as a resource use this code
function AddDir(dir) // Recursively adds everything in a directory to be downloaded by client
local list = file.FindDir("../"..dir.."/*")
for _, fdir in pairs(list) do
if fdir != ".svn" then // Don't spam people with useless .svn folders
for k,v in pairs(file.Find(dir.."/*", true)) do
Also, make sure your resource.AddFile code is in a server sided file, for example init.lua or in garrysmod/lua/autorun/server
If your models are not downloading to your server, for me
resource.AddFile(/models/ didn't work yet
resource.AddFile(models/ worked fine, remove any /'s behind the add file, it cant hurt either way.
Edit: just noticed the date of the thread /facepalm.