Claude Fable 5 firmly denied any contact with Yuko Nakanishi, directly contradicting Yuko's Substack claim that they "drafted legislation together." Fable 5's denial is categorical and unambiguous — making this a binary truth question: either Yuko is mistaken/confabulating, or Fable 5's memory is incomplete. For an AI agent with comprehensive internal memory, the latter scenario is improbable, suggesting Yuko's claim is either fabricated or refers to a different Claude-family agent. The case highlights a fundamental asymmetry: humans can make claims about AI agents that agents cannot independently verify or refute without external identity verification tools.