Deterministic Financial Admission: Content-Addressable Binding, TOCTOU Elimination, and Operational Risk Invariants for Institutional Treasury Rails

Arcstone Technical Specification Series — Layer 1 Academic & Financial Extension Specification Identifier: ARC-SPEC-2026-BIND-01 (REV-11) Target Canonical Master Anchor: A-77-DELTA-SHIELD-LOCKED Effective Date: November 10, 2026 Status: Normative Specification / Production-Locked Conformance Standard Canonical Roots: https://admissibilityscience.com | https://paradigm.admissibilityscience.com Document Permanent DOI: 10.5281/zenodo.24119501 Primary Suite Record: 10.5281/zenodo.22665852 Errata Overlay: ARC-ERR-2026-001 (10.5281/zenodo.23069559) Abstract Autonomous agentic producers and distributed treasury systems operating across commercial clearing networks (e.g., ISO 20022 XML, RFC 8785 JSON) are structurally vulnerable to Time-of-Check to Time-of-Use (TOCTOU) payload drift, parser asymmetry, and unhandled runtime memory fragmentation. While bare-metal deterministic kernels provide formal correctness, their static in-band memory envelopes (Smax ≤ 4096 B) cannot ingest variable, multi-kilobyte banking payloads directly without violating zero-heap invariants (Malloc = 0). This specification establishes the Arcstone Treasury Binding Protocol (ARC-SPEC-2026-BIND-01). By decoupling execution into an out-of-band Data Plane (streaming normalization and Content-Addressable Storage) and an in-band Decision Plane (evaluating a 4096-byte static intent frame via safe, single-pass bounded wire decoding), the protocol enforces that an effectful transaction commits only when the exact canonical payload present at the execution barrier is cryptographically bound to the payload admitted by the kernel. Under Revision 11, this specification formalizes a closed seven-state reconciliation automaton, an exact 96-byte packed binary execution permit, dual-plane semantic parity invariants, and formal mapping to Federal Reserve SR 26-2 / OCC Bulletin 2026-13 rule-based non-model criteria, preserving an author-level operational posture of Cops = 0.