You've got the model right. And saving prompt logs does help with reconstruction.

But warrants aren't just "more audit data." They're an authorization primitive enforced in the critical path: scope and constraints are checked mechanically before the action executes. The receipt is a byproduct.

Prompt logs tell you what the model claimed it was doing. A warrant is what the human actually authorized, bound to an agent key, verifiable without trusting the agent runtime.

This matters more in multi-agent systems. When Agent A delegates to Agent B, which calls a tool, you want to be able to link that action back to the human who started it. Warrants chain cryptographically. Each hop signs and attenuates. The authorization provenance is in the artifact itself.