Run ONE named check against a response you paste

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x885E7BEF433eb78F5976b28A7c10739c98DB11E5",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "4000",
    "maxTimeoutSeconds": 60
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "payTo": "6Cg4g7rXQApimMc9wVJGLLZfHsvbwGpGrUpGDgyJ2RaP",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "4000",
    "maxTimeoutSeconds": 60
  }
]

{
  "bazaar": {
    "info": {
      "input": {
        "body": "{\"status\":402,\"headers\":{\"content-type\":\"application/json\"},\"body\":\"{\\\"x402Version\\\":1,\\\"accepts\\\":[{\\\"scheme\\\":\\\"exact\\\",\\\"network\\\":\\\"base\\\",\\\"maxAmountRequired\\\":\\\"1000\\\",\\\"resource\\\":\\\"https://example.com/api/thing\\\",\\\"description\\\":\\\"an example paid endpoint\\\",\\\"mimeType\\\":\\\"application/json\\\",\\\"payTo\\\":\\\"0x0000000000000000000000000000000000000001\\\",\\\"maxTimeoutSeconds\\\":60,\\\"asset\\\":\\\"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913\\\",\\\"extra\\\":{\\\"name\\\":\\\"USD Coin\\\",\\\"version\\\":\\\"2\\\"},\\\"outputSchema\\\":{\\\"input\\\":{\\\"type\\\":\\\"http\\\",\\\"method\\\":\\\"POST\\\",\\\"discoverable\\\":true,\\\"bodyType\\\":\\\"text\\\",\\\"description\\\":\\\"the request body\\\"},\\\"output\\\":{\\\"type\\\":\\\"string\\\",\\\"description\\\":\\\"the response body\\\"}}}]}\",\"check\":\"V2_HEADER_PRESENT\"}",
        "bodyType": "text",
        "method": "POST",
        "type": "http"
      },
      "output": {
        "example": "{\"check\":\"V2_HEADER_PRESENT\",\"applied\":true,\"passed\":false,\"finding\":{\"severity\":\"error\",\"code\":\"V2_HEADER_PRESENT\",\"message\":\"no PAYMENT-REQUIRED response header — this endpoint publishes no x402 v2 envelope.\",\"fix\":\"Add a PAYMENT-REQUIRED response header to the 402 carrying the standard-base64 JSON v2 envelope. This costs you DISCOVERY rather than payment, and the distinction is worth being precise about: @x402/core reads the header first but DOES fall back to a v1 body when there is none, so the current client generation can still pay you. What it cannot do is find you — CDP marks the PAYMENT-REQUIRED header a required indexing check, so a v1-only 402 is not catalogued at all, and a strictly-v2 client cannot pay it either. Keep the v1 body exactly as it is; the two versions share a 402 without either noticing the other.\",\"core\":false,\"sources\":[{\"kind\":\"spec\",\"ref\":\"specs/transports-v2/http.md:7-25 § Payment Required Signaling\"},{\"kind\":\"cdp-validator\",\"ref\":\"cdp-validator-toolshed.json preflight[6] payment_required_header (required)\"},{\"kind\":\"client-code\",\"ref\":\"@x402/[email protected] dist/cjs/http/index.js:1620-1628 — the v2 client DOES fall back to a v1 body\"},{\"kind\":\"field-report\",\"ref\":\"x402-foundation/x402#3091 — [email protected] is still a live buyer population\"}]},\"regime\":\"bazaar\",\"severity\":\"error\",\"core\":false,\"sources\":[{\"kind\":\"spec\",\"ref\":\"specs/transports-v2/http.md:7-25 § Payment Required Signaling\"},{\"kind\":\"cdp-validator\",\"ref\":\"cdp-validator-toolshed.json preflight[6] payment_required_header (required)\"},{\"kind\":\"client-code\",\"ref\":\"@x402/[email protected] dist/cjs/http/index.js:1620-1628 — the v2 client DOES fall back to a v1 body\"},{\"kind\":\"field-report\",\"ref\":\"x402-foundation/x402#3091 — [email protected] is still a live buyer population\"}],\"summary\":{\"versions_detected\":[1],\"payTo\":\"0x0000000000000000000000000000000000000001\",\"network\":\"base\",\"price\":\"$0.001 (1000 atomic)\"},\"checks_run\":1}",
        "format": "application/json",
        "type": "text"
      }
    },
    "schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "input": {
          "additionalProperties": false,
          "properties": {
            "body": {
              "description": "a JSON object: { \"status\": 402, \"headers\": { … }, \"body\": \"…\", \"check\": \"V2_B64_URLSAFE\" } — exactly one check id from GET /check, up to 256 KB",
              "maxLength": 262144,
              "type": "string"
            },
            "bodyType": {
              "const": "text",
              "type": "string"
            },
            "method": {
              "const": "POST",
              "type": "string"
            },
            "type": {
              "const": "http",
              "type": "string"
            }
          },
          "required": [
            "type",
            "method",
            "bodyType",
            "body"
          ],
          "type": "object"
        },
        "output": {
          "additionalProperties": false,
          "properties": {
            "example": {
              "description": "the sample request body above, actually run through this endpoint — or, when that run is larger than a response header should carry, an object naming its size and the free URL it is published at in full",
              "type": "string"
            },
            "format": {
              "const": "application/json",
              "description": "a JSON single-check report: check, applied, passed, the finding with its fix (or null), regime, sources and the envelope summary",
              "type": "string"
            },
            "type": {
              "const": "text",
              "type": "string"
            }
          },
          "required": [
            "type",
            "format"
          ],
          "type": "object"
        }
      },
      "required": [
        "input"
      ],
      "type": "object"
    }
  }
}

curl "https://10x402.com/lint/envelope/one"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

const res = await fetch("https://10x402.com/lint/envelope/one");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

import httpx
res = httpx.get("https://10x402.com/lint/envelope/one")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header