It would be the same as you made your store command. The only difference being is a checkbox "Must have valid CURRENT_ITEM" or something of the like. If the current_item is not found (just as the debug error explains) then it'll print "Invalid Command" for the player.
I also have to clarify that CURRENT_ITEM has to be present in the CURRENT_LOCATION to be valid. If you're trying to move items from one storage to another without the item being present in the current location, I'll have to add a new reserved word for that scenario.