{"query":"merkle-verify","valid":true,"source":"stream-2-a2a/proof-merkle-fixture","route":"/api/v1/proof/merkle-verify","sample":true,"cost":"free","paidPriceUsd":"0.05","fieldsIncludedWhenPaid":["leaf","proof","root"],"note":"Free sample: this preview costs nothing. POST /api/v1/proof/merkle-verify?leaf=<text>&proof=[...]&root=<hex> charges 0.05 USDC and returns the same shape plus the caller-supplied leaf, proof and root."}