Parent State ID: 13
State Depth: 7
Action Taken: unstack(a, d)
Action Reasoning: To stack block 'd' on block 'b', clear block 'd' from under 'a' by unstacking 'a'.
State Description: Block `a` is in the hand and is no longer clear. Block `b` is on the table and is clear. Block `c` is on the table and is clear. Block `d` is on the table and is clear. The hand is holding block `a`.
Action Path: ['unstack(d, a)', 'put-down(d)', 'unstack(a, c)', 'stack(a, d)', 'unstack(c, b)', 'put-down(c)', 'unstack(a, d)']

INACTIVE REASON: deactivated because diagram generation failed or invalid action chosen: The action unstack(a, d) does not align with the goal state as it removes block_a from block_d, contrary to the goal requirements.
