Organizations and individuals increasingly delegate consequential action—email, iden-tity, payments, hiring, clinical triage—to autonomous AI agents supplied by many inde-pendent vendors. No vendor holds end-to-end visibility into the delegator's intent, ac-tions, and consequences, so each optimizes its own metrics behind an opaque boundary. The result is coherence debt: the accumulating, largely invisible gap between what a principal expects its delegated actions to produce and what they actually produce. Be-cause AI acts at machine speed, this debt compounds faster than fragmented human oversight can detect it, and its consequences arrive with greater gravity and less warning.
This article states the problem precisely, surveys the current state of practice and the emerging architectural response, and sets out what remains to be built and demonstrated. It formalizes coherence debt as unreconciled, severity-weighted divergence, and shows—via a requisite-variety argument—that governance bolted on externally cannot close the gap in principle. It then distinguishes two loci of the problem: intra-system co-herence debt, which the emerging Mindful Machines paradigm addresses by making governance an intrinsic architectural property (a Digital Genome, an autopoietic control system, and a continuous Discover–Reflect–Apply–Share loop), and boundary coherence debt, which no current approach closes. It proposes the Sovereignty Boundary Ledger, a six-layer reference architecture that extends intrinsic-governance discipline across the trust boundary to agents the principal cannot rewrite, and it specifies concretely what is already demonstrated and what is required to demonstrate the approach at enterprise scale.