402api Seller Check
Call before paying an unfamiliar x402 endpoint, or to pick between providers. $0.02, usually <1 s plus one probe: live unpaid probe (status, latency, TLS, PAYMENT-REQUIRED decoded and sanity-checked), seller reputation from indexed on-chain USDC payments to its Base payTo (24 h/7 d count, distinct payers, total and median USD, top-payer share), Bazaar listing and price, and a looks legit/caution/avoid verdict citing each fact. Errors: 400/503 JSON {error}, not charged.
Offering
- Provider
- tokencheck.402api.dev
- Method
- GET
- Offering type
- Api Endpoint
- Transport type
- http
- Category
- Blockchain And Crypto
- Delivery
- Not provided
- Pricing model
- Not provided
- x402 version
- 2
Endpoint context
- URL
https://tokencheck.402api.dev/v1/seller-check- MIME type
- application/json
- First seen
- 2026-10-16T01:50:32.458Z
- Last seen
- Tags
- X402, seller-reputation, Trust, provider-selection, pre-payment-check, Base, USDC
Payment pricing
x402 payment terms are the authoritative price for calling this endpoint.
- Payment option 1
- 0.02 USDC
Atomic price: 20000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Raw x402 terms
[
{
"scheme": "exact",
"network": "eip155:8453",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"amount": "20000",
"payTo": "0x8C8A81E2acEc6ed62421f1f4E7125B0b84FFffdE"
}
]Observed health
- Status
- Healthy
- Latest latency
- 309 ms
- Average latency
- 806 ms
- HTTP status
- 402
- Last checked
- Reachability
- 100% over 14 checks
Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.
Input schema
{
"type": "object",
"properties": {
"type": {
"type": "string",
"const": "http"
},
"method": {
"type": "string",
"enum": [
"GET"
]
},
"queryParams": {
"type": "object",
"properties": {
"url": {
"type": "string",
"pattern": "^https?://",
"maxLength": 2048,
"description": "The x402 resource URL you are about to pay (http/https). Give this or payTo."
},
"payTo": {
"type": "string",
"pattern": "^0x[0-9a-fA-F]{40}$",
"description": "A seller's Base payTo address (reputation + its most-called Bazaar resource is probed). Give this or url."
}
}
},
"discoverable": {
"const": true
}
},
"required": [
"type",
"method"
],
"additionalProperties": false
}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"
}