Parent State ID: 22
State Depth: 7
Action Taken: stack(b, a)
Action Reasoning: To get closer to the goal state, we should stack block 'b' on block 'a' since 'a' is already on 'c' and clear, aligning with the goal configuration.
State Description: Block 'b' is now on block 'a', which is on block 'c'. Block 'a' becomes not clear, and block 'b' is clear. Block 'd' remains on the table and clear. The hand is empty.
Action Path: ['unstack(c, d)', 'put-down(c)', 'unstack(d, a)', 'put-down(d)', 'pick-up(a)', 'stack(a, c)', 'stack(b, a)']

INACTIVE REASON: deactivated because diagram generation failed or invalid action chosen: The hand is not holding block 'b', violating the precondition for the stack action.
