When you either go to bed or log out with tools in your hot bar, one of the tools when you select it will look like another; such as if a pick and shovel are in your hot bar, the pick when you select it it will come up in your hand as a shovel. But i still mines and doesn't he things it is suposed to do. I actually dont really know how it does this but i assume it happenes when you go to bed or log out, im not sure. Sorry