Parent State ID: 24
State Depth: 8
Action Taken: stack(b, c)
Action Reasoning: To progress toward the goal, block 'b' should be placed on block 'c', which will make 'a', 'b', and 'c' stacked in the right order.
State Description: The hand is now empty. Block 'b' is on block 'c' and clear. Block 'a' remains on block 'c' and is not clear. Block 'c' is on the table and not clear. Block 'd' is on the table and clear.
Action Path: ['unstack(c, d)', 'put-down(c)', 'unstack(d, a)', 'put-down(d)', 'pick-up(a)', 'stack(a, c)', 'pick-up(b)', 'stack(b, c)']

INACTIVE REASON: deactivated because diagram generation failed or invalid action chosen: Block 'c' is not clear, violating preconditions for stacking.
