diff --git a/doc/en/scripting/ui.md b/doc/en/scripting/ui.md
index 02cebe709..22a878944 100644
--- a/doc/en/scripting/ui.md
+++ b/doc/en/scripting/ui.md
@@ -241,6 +241,7 @@ Properties:
 
 Properties:
 
-| Name      | Type | Read | Write | Description                                       |
-| --------- | ---- | ---- | ----- | ------------------------------------------------- |
-| inventory | int  | yes  | no    | id of the inventory to which the element is bound |
+| Name      | Type | Read | Write | Description                                        |
+| --------- | ---- | ---- | ----- | -------------------------------------------------- |
+| inventory | int  | yes  | no    | id of the inventory to which the element is bound  |
+| slotIndex | int  | yes  | no    | index of the slot to which the element is attached |
diff --git a/doc/ru/scripting/ui.md b/doc/ru/scripting/ui.md
index 4d1fee695..05b448a43 100644
--- a/doc/ru/scripting/ui.md
+++ b/doc/ru/scripting/ui.md
@@ -244,4 +244,5 @@ Canvas.decode(data: Bytearray, format: str) -> Canvas
 | Название  | Тип | Чтение | Запись | Описание                                  |
 |-----------|-----|--------|--------|-------------------------------------------|
 | inventory | int | да     | нет    | id инвентаря, к которому привязан элемент |
+| slotIndex | int | да     | нет    | индекс слота, к которому примязан элемент |