Parent State ID: 20
State Depth: 9
Action Taken: stack(a, c)
Action Reasoning: To achieve the goal state, block 'c' needs to be on the table and block 'a' stacked on top of it. The first step is to stack 'a' onto 'c' as both are clear and on the table. This move brings us closer to the goal configuration.
State Description: Block 'a' is on top of block 'c'. Block 'c' is on the table and is not clear. Block 'a' is clear. Blocks 'b' and 'd' are on the table, both are clear. The hand is empty.
Action Path: ['unstack(b, c)', 'put-down(b)', 'unstack(c, d)', 'put-down(c)', 'unstack(d, a)', 'put-down(d)', 'pick-up(a)', 'put-down(a)', 'stack(a, c)']

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