[2603.28735] RAD-AI: Rethinking Architecture Documentation for AI-Augmented Ecosystems

Computer Science > Software Engineering arXiv:2603.28735 (cs) [Submitted on 30 Mar 2026] Title:RAD-AI: Rethinking Architecture Documentation for AI-Augmented Ecosystems Authors:Oliver Aleksander Larsen, Mahyar T. Moghaddam View a PDF of the paper titled RAD-AI: Rethinking Architecture Documentation for AI-Augmented Ecosystems, by Oliver Aleksander Larsen and 1 other authors View PDF HTML (experimental) Abstract:AI-augmented ecosystems (interconnected systems where multiple AI components interact through shared data and infrastructure) are becoming the architectural norm for smart cities, autonomous fleets, and intelligent platforms. Yet the architecture documentation frameworks practitioners rely on, arc42 and the C4 model, were designed for deterministic software and cannot capture probabilistic behavior, data-dependent evolution, or dual ML/software lifecycles. This gap carries regulatory consequence: the EU AI Act (Regulation 2024/1689) mandates technical documentation through Annex IV that no existing framework provides structured support for, with enforcement for high-risk systems beginning August 2, 2026. We present RAD-AI, a backward-compatible extension framework that augments arc42 with eight AI-specific sections and C4 with three diagram extensions, complemented by a systematic EU AI Act Annex IV compliance mapping. A regulatory coverage assessment with six experienced software-architecture practitioners provides preliminary evidence that RAD-AI increases Annex I...