It needs to be loaded on any client/server that has the AI as local. So, if you only have the server and nothing else, then only server needs it loaded.

If you have a Zeus, then that Zeus player(s) need to have it loaded.

If you have headless clients, then each of those need it loaded too.

That needs to be on the front page. It's pretty vital information.

Sorry, I do not understand.
On my server I put -serverMod=@lambs and the clients entered without -mod=@lambs. It doesn't seem to work.

I think you only need to have the mod enabled server side for it to work, and enabled client side only for admins who want to be able to manage the server settings in the options menu. That's what I did and it seemed to work fine--I had it enabled as a server mod, and also enabled client side for me (so I could manage the settings as an admin) and I had someone join the server who didn't have the LAMBS mod enabled and everything seemed to work fine.

I am managing my server using FASTER. Since my server does key verification for mods, the first thing I did was enable the mod client side by checking the box, and then I clicked the button to copy over all the keys (FASTER doesn't seem to copy the key file unless it is enabled as a client mod). After I copied the key file, I unchecked the box to enable LAMBS as a client mod, and enabled it as a server side mod. Then, I saved the settings and started the server.