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

Action Reasoning:
The goal is to have block 'd' on block 'b'. Since the hand is holding block 'd' and block 'b' is clear, the best action is to stack 'd' on 'b'.

New State Description:
Block 'd' is on block 'b', and the hand is empty. Block 'b' is supporting block 'd' and is no longer clear. Block 'a' is on block 'c' and is clear. Block 'c' is supporting block 'a' and is no longer clear.

Action Chosen:
stack(d, b)
