Interrupted Agents Need a Recoverability Contract, Because Accurate Restoration Can Still Hide a Disallowed Starting Point

arXiv 2609.13672·medium signalXBlueskyLinkedInCopy link

Agents get interrupted mid-edit or mid-tool-call, and both options are bad: restarting repeats finished work, continuing from unverified progress carries earlier errors forward. This paper makes reuse an explicit decision, binding the choice of starting point and permitted recovery action to supporting evidence, execution and independent checks. Four deterministic and 20 paired file challenges show that accurate restoration and successful task completion can conceal a disallowed starting point, and event-time tests show permission has to constrain the recovery action itself, not just the restored bytes.