diff --git a/internal.lua b/internal.lua
index 06967d2..3fad275 100644
--- a/internal.lua
+++ b/internal.lua
@@ -223,7 +223,8 @@ function unified_inventory.get_formspec(player, page)
 		for y = 0, ui_peruser.pagerows - 1 do
 			for x = 0, ui_peruser.pagecols - 1 do
 				local name = unified_inventory.filtered_items_list[player_name][list_index]
-				if minetest.registered_items[name] then
+				local item = minetest.registered_items[name]
+				if item then
 					-- Clicked on current item: Flip crafting direction
 					if name == unified_inventory.current_item[player_name] then
 						local cdir = unified_inventory.current_craft_direction[player_name]
@@ -236,12 +237,18 @@ function unified_inventory.get_formspec(player, page)
 					-- Default: use active search direction by default
 						dir = unified_inventory.active_search_direction[player_name]
 					end
-					formspec[n] = "item_image_button["
-						..(8.2 + x * 0.7)..","
-						..(ui_peruser.formspec_y + ui_peruser.page_y + y * 0.7)..";.81,.81;"
-						..name..";item_button_"..dir.."_"
-						..unified_inventory.mangle_for_formspec(name)..";]"
-					n = n+1
+
+					local button_name = "item_button_" .. dir .. "_"
+						.. unified_inventory.mangle_for_formspec(name)
+					formspec[n] = ("item_image_button[%f,%f;.81,.81;%s;%s;]"):format(
+						8.2 + x * 0.7, ui_peruser.formspec_y + ui_peruser.page_y + y * 0.7,
+						name, button_name
+					)
+					formspec[n + 1] = ("tooltip[%s;%s \\[%s\\]]"):format(
+						button_name, minetest.formspec_escape(item.description),
+						item.mod_origin or "??"
+					)
+					n = n + 2
 					list_index = list_index + 1
 				end
 			end