Parent State ID: 74
State Depth: 11
Action Taken: pick-up(block_b)
Action Reasoning: To achieve the goal state, we need to stack block B on block D. First, we need to hold block B. Since block B is clear and on the table, we can pick it up.
State Description: Block A is on the table and clear. Block B is held by the hand and not clear. Block C is on the table and not clear, with block D stacked on it. Block D is on block C and clear. The hand is holding block B.
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)', 'pick-up(block_b)']

INACTIVE REASON: action path invalid: The last action `pick-up(block_b)` is invalid because its preconditions are not met: `block_b` is not clear, not on the table, and the hand is not empty. However, the current state's natural language description and visualization are accurate.
