Constraint-first string theory: the flux landscape's only exact structure is its constraint

We measure, on real supersymmetric flux vacua, which low-energy observables carry information about the flux that produced them. The result is a structure map: the string coupling, gauge couplings, mass-spectrum shape, axions, dilaton and cosmological constant are statistically uniform in flux; exactly one quantity is exactly structured — the D3 tadpole, the symplectic pairing N_flux = F^T J H (r = 1.0). The landscape's only exact structure is what it forbids, not what it selects.