Parent State ID: 61
State Depth: 10
Action Taken: stack(block_d, block_c)
Action Reasoning: To achieve the goal state, we need to stack the blocks in the order D on C, B on D, and A on B. Currently, block D is held by the hand. The best immediate action is to stack block D onto block C, as this matches part of the goal state.
State Description: Block A is on the table and clear. Block B is on the table and clear. Block C is on the table and not clear, as block D is on it. Block D is on block C and clear. 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)', 'stack(block_b, block_c)', 'unstack(block_b, block_c)', 'put-down(block_b)', 'pick-up(block_d)', 'stack(block_d, block_c)']

INACTIVE REASON: action path invalid: The last action `stack(block_d, block_c)` is invalid because the precondition that the hand must be holding `block_d` is not met. The hand is empty, and `block_d` is already on `block_c`.
