when you sneak and break a block it activates depending on what tool you use if you mine down or up with a pickake you make a automatic staircase if you look at any non ore block with a pickaxe while sneaking and i must say that you have to be sneaking while breaking the block for this to work it will make an automatic strip mine when you mine a log with an axe it will break the whole tree and any trees connected to it everything will make the durrability on your tool go down
the autominer is also activated when you hold down crouch with the tag of automine