@Mod.EventBusSubscriber(modid = ProjectDawn.MOD_ID)
public class CapabilityHandler {

    public CapabilityHandler() {}

    @SubscribeEvent
    public static void onAttachCapabilitiesEvent(AttachCapabilitiesEvent<ItemStack> event)
    {
        if(((ItemStack)event.getObject()).getItem() instanceof AbstractStaffItem) {
            StaffProvider provider = new StaffProvider();
            event.addCapability(new ResourceLocation(ProjectDawn.MOD_ID, "cast_sound"), provider);
            event.addCapability(new ResourceLocation(ProjectDawn.MOD_ID, "empty_sound"), provider);
            event.addListener(provider::invalidate);
        }

    }

}