AARC: A Machine-Verifiable Audit and Reliability Contract for Tool-Using AI Agents

AARC (Agentic Audit & Reliability Contract) is a model- and policy-engine-independent runtime contract for externally observable execution by tool-using AI agents. It defines machine-verifiable runtime-event and state-vector schemas, immutable role, objective, and policy anchors, RFC 8785 canonical event commitments, fail-closed tool authorization receipts, separated Actor–Critic–Judge decision validation, and append-only change provenance. The accompanying artifact provides executable Python and TypeScript reference monitors, JSON Schema validation, cross-language canonicalization vectors, adversarial fault injection, and a reproducible publication pipeline. The deterministic conformance suite accepts the clean reference trace and rejects all 11 injected structural and semantic violations, including attacks whose hash chains are recomputed after mutation. AARC conformance establishes enforcement of the stated execution-contract invariants; it does not by itself establish factual correctness, policy quality, provenance authenticity, or general agent safety. Version provenance: AARC v1.1.0 was publicly committed on September 25, 2026 at Git commit 3aa462a04dd5d0b5778012577fd379e34bd0e71f. AARC v1.1.1, released October 2, 2026, updates literature positioning and publication metadata while leaving the normative AARC v1.1.0 runtime contract, schemas, reference-monitor semantics, and September 25 evaluation results unchanged.