Parent State ID: 22
State Depth: 7
Action Taken: pick-up(b)
Action Reasoning: To achieve the goal state, we need to stack block 'b' on block 'a'. Since block 'b' is clear and the hand is empty, we can pick up block 'b' as the next step.
State Description: The hand is now holding block 'b'. Block 'a' remains on block 'c' and is clear. Block 'c' is not clear. Block 'd' is on the table and clear. Block 'b' is no longer on the table and is not clear.
Action Path: ['unstack(c, d)', 'put-down(c)', 'unstack(d, a)', 'put-down(d)', 'pick-up(a)', 'stack(a, c)', 'pick-up(b)']
