x402 Inspector scan (payment-challenge validation) — per call

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x4eba5ea3cf0f3fc307099317e17e54390f7a4c58",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "20000",
    "maxTimeoutSeconds": 300
  }
]

{
  "bazaar": {
    "info": {
      "input": {
        "method": "POST",
        "schema": {
          "properties": {
            "url": {
              "description": "URL of the x402-protected endpoint to scan",
              "type": "string"
            }
          },
          "required": [
            "url"
          ],
          "type": "object"
        },
        "type": "http"
      },
      "output": {
        "example": {
          "details": {
            "accepts": [
              {
                "maxAmountRequired": "20000",
                "network": "base",
                "scheme": "exact"
              }
            ],
            "httpStatus": 402,
            "methodUsed": "GET",
            "x402Version": 2
          },
          "evidence": [
            "Responded 402 with a well-formed x402 payment challenge"
          ],
          "status": "valid",
          "target": "https://example.com/paid-endpoint",
          "warnings": []
        },
        "schema": {
          "properties": {
            "details": {
              "description": "methodUsed, httpStatus, x402Version, accepts[]",
              "type": "object"
            },
            "evidence": {
              "items": {
                "type": "string"
              },
              "type": "array"
            },
            "expectedResult": {
              "description": "Declared response shape, if the seller published a Bazaar discovery extension",
              "type": "object"
            },
            "status": {
              "description": "valid, invalid, malformed, or no_challenge",
              "type": "string"
            },
            "target": {
              "type": "string"
            },
            "warnings": {
              "items": {
                "type": "string"
              },
              "type": "array"
            }
          },
          "type": "object"
        }
      }
    },
    "schema": {
      "properties": {
        "details": {
          "description": "methodUsed, httpStatus, x402Version, accepts[]",
          "type": "object"
        },
        "evidence": {
          "items": {
            "type": "string"
          },
          "type": "array"
        },
        "expectedResult": {
          "description": "Declared response shape, if the seller published a Bazaar discovery extension",
          "type": "object"
        },
        "status": {
          "description": "valid, invalid, malformed, or no_challenge",
          "type": "string"
        },
        "target": {
          "type": "string"
        },
        "warnings": {
          "items": {
            "type": "string"
          },
          "type": "array"
        }
      },
      "type": "object"
    }
  }
}

curl "https://contextiq.trango-compute.com/api/v1/x402-inspector/x402-v2"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

const res = await fetch("https://contextiq.trango-compute.com/api/v1/x402-inspector/x402-v2");
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://contextiq.trango-compute.com/api/v1/x402-inspector/x402-v2")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header