Parent State ID: 39
State Depth: 9
Action Taken: pick-up(b)
Action Reasoning: To achieve the goal state, we need to move block 'b' onto block 'a'. Since block 'a' is clear, we can pick up block 'b' from the table and stack it on block 'a'.
State Description: The hand is holding block 'b'. Block 'd' is on block 'b' and is clear. Block 'b' is no longer on the table and is not clear. Block 'a' is on block 'c' and is clear. Block 'c' is supporting block 'a' and is no longer clear.
Action Path: ['unstack(c, d)', 'put-down(c)', 'unstack(d, a)', 'stack(d, b)', 'pick-up(a)', 'stack(a, c)', 'unstack(d, b)', 'stack(d, b)', 'pick-up(b)']

INACTIVE REASON: deactivated because diagram generation failed or invalid action chosen: Block 'b' is not clear, violating the precondition for pick-up.
