This study introduces AICOS® as a governance-first Decision Intelligence infrastructure designed for replayable, audit-ready, and human-final institutional artificial intelligence systems. The paper examines the growing governance challenges associated with opaque AI-driven decision environments and proposes a framework integrating deterministic replayability, evidence continuity, uncertainty-aware governance controls, bounded authority structures, and fail-closed operational logic into institutional AI architecture. The proposed framework positions governance not as an external compliance layer, but as a foundational operational principle embedded directly into the decision lifecycle itself. The study further explores institutional applications within financial systems, banking infrastructures, and high-accountability operational environments where auditability, operational transparency, and supervisory continuity are critical requirements. The paper contributes to the literature surrounding trustworthy AI, institutional governance systems, operational accountability infrastructures, and replay-oriented decision architectures. It argues that future institutional AI systems should be evaluated not only according to predictive performance, but also according to replayability, governance resilience, audit continuity, and preservation of institutional trust under uncertainty.

AICOS® is presented as a governance-first institutional Decision Intelligence framework focused on preserving operational accountability, replay continuity, bounded authority, and institutional trust within high-impact AI-assisted environments. The architecture integrates deterministic replay infrastructure, evidence-chain preservation, uncertainty-aware governance mechanisms, fail-closed operational controls, and human-final supervisory authority into a unified institutional framework. The study is particularly relevant for regulated sectors including banking, financial technology, insurance, public-sector governance, cybersecurity, and critical infrastructure systems where explainability, auditability, and operational resilience are essential organizational requirements. This publication is part of the broader AICOS® research initiative focused on governance-centered institutional artificial intelligence, replayable decision systems, and operational trust infrastructures for complex organizational environments.