Parent State ID: 17
State Depth: 7
Action Taken: pick-up(d)
Action Reasoning: To achieve the goal state, we need to move block 'b' onto block 'a'. First, we need to clear block 'b' by removing block 'd' from it. Since block 'd' is clear, we can pick it up.
State Description: The hand is holding block 'd'. Block 'b' is now clear and on the table. Block 'a' is on block 'c' and is clear. Block 'c' is supporting block 'a' and is not clear.
Action Path: ['unstack(c, d)', 'put-down(c)', 'unstack(d, a)', 'stack(d, b)', 'pick-up(a)', 'stack(a, c)', 'pick-up(d)']

INACTIVE REASON: deactivated because diagram generation failed or invalid action chosen: Block 'd' is not on the table, violating the precondition for pick-up.
