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

Action Reasoning:
To progress toward the goal, I will first put down block 'd' so that the hand becomes free, allowing me to move 'a' on top of 'c'.

New State Description:
Block 'a' is on the table and clear. Block 'b' is clear and on block 'c'. Block 'c' is on the table, supporting block 'b'. Block 'd' is now on the table and clear. The hand is empty.

Action Chosen:
put-down(block_d)
