Parent State ID: 30
State Depth: 8
Action Taken: stack(d, b)
Action Reasoning: The first step towards achieving the goal state is to place block `d` on block `b` directly, as required by the final configuration.
State Description: Block `a` is on the table and clear. Block `b` is on the table and supports block `d`. Block `c` is on block `b` and is clear. Block `d` is on block `b` and is clear. The hand is empty.
Action Path: ['unstack(d, a)', 'put-down(d)', 'unstack(a, c)', 'put-down(a)', 'pick-up(d)', 'put-down(d)', 'pick-up(d)', 'stack(d, b)']

INACTIVE REASON: deactivated because diagram generation failed or invalid action chosen: Block `b` is not clear, violating the precondition for stacking.
