Optional
The block the bot is placing against (the block being clicked).
from field: soulfire.v1.BlockPosition against = 3;
from field: string bot_id = 2;
Which face of against is being clicked. The new block is placed adjacent to that face.
against
from field: soulfire.v1.BlockFace face = 4;
Which hand holds the item being placed.
from field: soulfire.v1.Hand hand = 5;
from field: string instance_id = 1;
from message soulfire.v1.PlaceBlockRequest
The block the bot is placing against (the block being clicked).