Buyer-side trust oracle for the x402 marketplace: 'I need X, budget $Y — which tool is real?' Sweeps the WHOLE catalog across many queries, collapses sybil/factory clusters (one wallet stamping many fake-distinct listings), ranks the genuinely-used survivors by unique-payer usage, and returns one vetted pick with a ready-to-pay challenge. The credit-bureau check an agent can't do in a single query.