Parent State ID: 20
State Depth: 5
Action Taken: pick-up(block_d)
Action Reasoning: To achieve the goal state, block C should be on the table with block D on top of it. Block C is already on the table and clear, so we should place block D on block C next.
State Description: Block A is on the table and clear. Block B is on block D and clear. Block C is on the table and clear. Block D is held by the hand and clear. The hand is holding block D.
Action Path: ['unstack(block_b, block_c)', 'stack(block_b, block_d)', 'unstack(block_b, block_d)', 'stack(block_b, block_d)', 'pick-up(block_d)']

INACTIVE REASON: deactivated because diagram generation failed or invalid action chosen: block_d is not clear, so pick-up(block_d) is invalid.
