Digging is not mining
A block breaking and an item arriving in an inventory are two separate events. Treat them as one and a mining skill can look flawless and still come home with nothing.
In Minecraft, breaking a block does not hand its drop to whoever broke it. It spawns an item entity on the ground at the block's position, and that item has to be walked over and picked up like any other dropped item. This is easy to forget, because a player standing close to what they are breaking picks the drop up automatically, almost without noticing. A bot that breaks the same block from three steps back is well within reach to swing a pickaxe and well outside pickup range once the item lands. It walks away from a perfectly executed dig with an empty inventory.
So every mining and gathering skill in Cubelings is scored on a measured inventory delta, never on whether the block broke. These two lines describe the same swing:
A skill that digs without collecting is worse than one that fails outright and says so, because it looks successful right up until someone checks the chest.
What a real trip involves
A trip sent to fetch iron does not dig straight down, because the block underfoot might be the ceiling of a lava pocket or the top of a long drop. It cuts a staircase instead. One measured run went 15 blocks down in 16 steps and placed 2 torches on the way, so nothing spawns in the dark behind it.
- blocks down
- 15
- steps
- 16
- torches placed
- 2
- there and back
- ~160s
It checks its tool before it swings. Mining iron with anything less than a stone pickaxe destroys the ore and gives back nothing, so a trip carrying the wrong tool is refused before it starts instead of being wasted underground. After breaking ore it walks over the drop rather than assuming the swing was the whole job, then goes back the way it came. Descent, mining and the walk home take around 160 seconds, 48.6 of them in the descent alone. No single step is slow. The trip is scored from the first step to the last.
The same rule runs through every skill on Capabilities: report what was measured to change, never what was attempted. Verification covers how it applies to builds.