JS.setInterfaceString(string name, string value)
Use this to set the text of the various elements of the user interface. The values allowed for the name are:
InventoryLabel, StatusLabel, PlacesObjectsLabel, CompassLabel InButtonLabel, OutButtonLabel EmptyListLabel, NothingSelectedLabel, TypeHereLabel, ContinueLabel
For example, to change the name of the player inventory:
JS.setInterfaceString("InventoryLabel", "You are holding")