Skeleton, drill-down, act, verify
From top to bottom: start with snapshot --skeleton, a depth 3 map with children_count on cut branches. Pick a node with a ref and children_count and run snapshot --root on it to read that region into the same snapshot. Act on a ref from the drill, such as click. Verify with wait, get, or a re-drill of the same root. Then loop back to act again or drill another region.
calling agent
starts with a shallow map
snapshot --skeleton
depth 3, children_count on cut branches
pick a node with ref_id and children_count
snapshot --root <ref>
same snapshot_id, new refs
act on a ref from the drill
click @s…:eN
or set-value, select, check
verify
wait, get, or re-drill
read the result back
next action
or region