{"slug":"tokencheck-402api-dev-v1-seller-check-3d8f24","title":"Call before paying an unfamiliar x402 endpoint, or to pick between providers","host":"tokencheck.402api.dev","method":"GET","resource":"https://tokencheck.402api.dev/v1/seller-check","category":"market","description":"Call before paying an unfamiliar x402 endpoint, or to pick between providers. $0.02, usually <1 s plus one probe: live unpaid probe (status, latency, TLS, PAYMENT-REQUIRED decoded and sanity-checked), seller reputation from indexed on-chain USDC payments to its Base payTo (24 h/7 d count, distinct p","price_listed":0.02,"price_asked":0.02,"state":"answering","state_label":"Answering","checks_7d":1,"answered_7d":1,"latency_ms_median":1483,"reported_calls_30d":0,"reported_payers_30d":0,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"discoverable":true,"method":"GET","queryParams":{"url":"https://tokencheck.402api.dev/v1/token-check"},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"discoverable":{"const":true},"method":{"enum":["GET"],"type":"string"},"queryParams":{"properties":{"payTo":{"description":"A seller's Base payTo address (reputation + its most-called Bazaar resource is probed). Give this or url.","pattern":"^0x[0-9a-fA-F]{40}$","type":"string"},"url":{"description":"The x402 resource URL you are about to pay (http/https). Give this or payTo.","maxLength":2048,"pattern":"^https?://","type":"string"}},"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"oneOf":[{"description":"HTTP 200: the seller report","properties":{"bazaar":{"description":"listed, listing (description, amount, 30-day calls/payers), other listings for the payTo","type":"object"},"cached":{"type":"boolean"},"index":{"type":"object"},"measuredAt":{"type":"string"},"notes":{"items":{"type":"string"},"type":"array"},"payTo":{"type":["string","null"]},"probe":{"description":"status, ms, tls, x402 (version, valid, accepts with recognised asset, usd, payTo)","type":["object","null"]},"query":{"type":"object"},"reasons":{"items":{"type":"string"},"type":"array"},"reputation":{"description":"last24h / last7d: payments, distinctPayers, totalUsd, medianUsd, topPayerShare, complete","type":["object","null"]},"verdict":{"enum":["looks legit","caution","avoid"]}},"required":["verdict","reasons","bazaar","measuredAt"],"type":"object"},{"description":"Error body. HTTP 400 = bad or missing input; HTTP 503 = check failed or timed out (25 s). The payment is not settled on errors, so the caller is not charged.","example":{"error":"query parameter `token` must be a 0x-prefixed 40-hex-digit Base token address"},"properties":{"error":{"description":"What went wrong, in plain words","type":"string"}},"required":["error"],"type":"object"}],"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-10-10","reachable":true,"status":402,"valid_402":true,"asked_usdc":0.02,"price_match":true,"latency_ms":1483,"error":null}],"description_full":"Call before paying an unfamiliar x402 endpoint, or to pick between providers. $0.02, usually <1 s plus one probe: live unpaid probe (status, latency, TLS, PAYMENT-REQUIRED decoded and sanity-checked), seller reputation from indexed on-chain USDC payments to its Base payTo (24 h/7 d count, distinct payers, total and median USD, top-payer share), Bazaar listing and price, and a looks legit/caution/avoid verdict citing each fact. Errors: 400/503 JSON {error}, not charged.","last_updated":"2026-10-10T15:25:21.104Z","schemes":["exact"]}