Parent State ID: 50
State Depth: 8
Action Taken: stack(block_b, block_d)
Action Reasoning: To progress towards the goal state, I will stack block B, currently held in the hand, onto block D, which is on the table and clear. This action helps in building the desired stack order, starting with block D on block C.
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 on the table and not 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)', 'stack(block_b, block_d)']

INACTIVE REASON: action path invalid: The last action 'stack(block_b, block_d)' violates the precondition that block_d must be clear. The current state's natural language description and visualization are accurate, but the action is invalid.
