Attempt Number: 2
Error Message: Action not unique compared to other actions chosen from this state before. Choose a new action

Action Reasoning:
Block 'd' needs to be placed on top of block 'a' to reach the goal state. Since block 'a' is clear, I will stack block 'd' on block 'a'.

New State Description:
The hand is empty. Block 'd' is on top of block 'a' and is clear. Block 'a' is on top of block 'c' and is not clear. Block 'b' is clear and on the table. Block 'c' is not clear and on the table.

Action Chosen:
stack(d, a)
