Hi,

My mod is a simple GUI mod to edit some properties of an item.

Basically, this is how the mod works :

-> The player selects an item and press a hotkey 
-> GUI Opens
-> A packet is sent to the server with informations about the selected item (position in the inventory)
-> The player changes values in the GUI 
-> The player press "Done" button 
-> GUI Closes 
-> A packet with updated informations is sent to the server 
-> The server updates the item

The server doesn't do much but the mod still have to be installed on the server, or it won't work. Is there a way to make the mod client-sided only ?

Ok, thanks for replying.

-> The server updates the item

 

That's not happening without a server mod. In general, the server is authoritative (keeps "real" data on a world and makes decisions about what to change) while clients are GUI terminals (display what the server says, and relay player input to the server for interpretation).

 

For the most part, the only local control is over display parameters. Hence, client-only mods tend toward X-ray vision hacks that can get you perma-banned from most servers. For that reason, every time someone shows up here asking about client-only modding (an attempt to circumvent server authority), it attracts special interest and (sometimes stern) warnings.

 

However, there are some useful information mods like recipe look-up that don't need anything on the server. If you wanted to do something like that, then you might find help here.