Parent State ID: 23
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' to prepare for stacking it on block 'a'.
State Description: The hand is holding block 'b'. Block 'a' is on block 'c', making block 'a' not clear. Block 'c' is supporting block 'a' and is not clear. Block 'd' remains 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)']
