Paper 2 — SCD + Security: Output Reference Boundary Structures in the AGI Era

This working paper introduces SCD + Security as a non-executable output reference boundary structure for the AGI era. Building on Paper 1 of the AGI Structural Alignment Series, which established BIFACE-Based Sentence Coordinate Documents as a coordinate-reference grammar, this paper addresses the next structural question: which roles, AI+AGI environments, and review contexts may reference which sentence, code, image-region, video-scene, subtitle, voice-segment, conversation, or revision-instruction coordinates, under what boundary conditions. The paper defines SCD + Security as a reference-boundary layer rather than a cybersecurity, authentication, encryption, access-control, storage, execution, evidence-confirmation, approval, consent, or legal-effect system. Its purpose is to prevent SCD/BIFACE coordinates from becoming unrestricted access paths or unintended authority references. This working paper is Paper 2 of the AGI Structural Alignment Series.