Current ICT infrastructures operate predominantly as reactive data conduits, lacking the cognitive agility required to autonomously interpret context, adapt to dynamic network conditions, and self-optimize for sustainability in the face of exponentially growing device density and security threats. The convergence of agentic artificial intelligence (AI), 6Gendogenous intelligence, and stringent carbon-neutrality mandates necessitates a fundamental architectural shift from "connected systems" to "intelligent ICT systems" capable of self-perception, reasoning, and orchestration. This paper proposes comprehensive conceptual architectural framework grounded in cognitive theory and ITU-T standards, extended with formal Markov Decision Process (MDP) models for multi-agent coordination.