State is a projection of an event log. You can always reconstruct how you got here.
This is not a novel idea. Event sourcing has been established practice in distributed systems for two decades. What is novel is applying it rigorously to agentic execution — treating every action an agent takes as an immutable event with a provenance tag.
The reasoning trace problem
An audit trail that captures what the agent did is tractable. An audit trail that captures what the agent understood is not — model internals are opaque, and generated reasoning traces are themselves outputs subject to confabulation.
We do not yet have a satisfying answer here. What we do have is the discipline to be honest about the gap.