Parent State ID: 59
State Depth: 9
Action Taken: stack(block_b, block_d)
Action Reasoning: Our goal is to build the stack starting with block C supporting block D, then block B, and finally block A on top. Block D is already correctly positioned on block C. To proceed, we should clear block D by stacking block B on block D to move closer to our goal.
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 supporting block D. Block D is on block C and supporting block B. The hand is empty.
Action Path: ['unstack(block_b, block_c)', 'stack(block_b, block_d)', 'unstack(block_b, block_d)', 'stack(block_b, block_d)', 'unstack(block_b, block_d)', 'put-down(block_b)', 'pick-up(block_d)', 'stack(block_d, block_c)', 'stack(block_b, block_d)']

INACTIVE REASON: deactivated because diagram generation failed or invalid action chosen: The hand is not holding block B, violating the precondition for stacking.
