The fundamental question — why is there something rather than nothing? — creates a double bind requiring both metaphysics and discipline. We derive five structural requirements that any adequate framework must satisfy and show they jointly constrain an architecture of determinate form: the necessitated genus. Part I presents the derivation. Part II presents one species — the Architecture for Rational Programmes (ARP, v0.5), a thirteen-section preamble governing any metaphysical research programme. The ARP's upward support protocol, reflexivity clause, and adversarial translation mechanism are architecturally novel. Its reflexivity provision requires programmes involving non-standard authorial agents to classify those agents within the programme's observer account or declare the gap. This paper enacts that provision: its authorship is composite, its observer classification is a declared standing anomaly, and both are within the scope of the architecture it presents.