All /obj/item(s) have a hidden_uplink var. By default it's null. Give the item one with 'new(src') (it must be in it's contents). Then add 'uses.' Use whatever conditionals you want to check that the user has an uplink, and then call interact() on their uplink. You might also want the uplink menu to open if active. Check if the uplink is 'active' and then interact() with it.