Parent State ID: 61
State Depth: 10
Action Taken: stack(block_d, block_c)
Action Reasoning: To achieve the goal state, block D needs to be placed on block C. This is why the next best action is to stack block D onto block C.
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 no longer clear because block D is on top of it. Block D is on top of 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 its preconditions are not met: the hand is not holding `block_d`, and `block_c` is not clear. The current state's description and visualization are accurate, but the action does not logically follow from the previous state.
