Parent State ID: 41
State Depth: 9
Action Taken: unstack(d, b)
Action Reasoning: To achieve the goal state, we need to move block 'b' onto block 'a'. Since block 'd' is currently on block 'b', we should first unstack 'd' from 'b' to make 'b' clear.
State Description: The hand is holding block 'd'. Block 'b' is now clear and on the table. Block 'a' is on block 'c', and block 'c' is on the table. The diagram will show block 'd' being held by the hand, with block 'b' clear and on the table.
Action Path: ['unstack(c, d)', 'put-down(c)', 'unstack(d, a)', 'stack(d, b)', 'pick-up(c)', 'put-down(c)', 'pick-up(a)', 'stack(a, c)', 'unstack(d, b)']
