Signed multi-chain OFAC SDN address screening (USDC on Base or Solana)

[
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "payTo": "35tCuyL3E7M88jfhTeEaRxhrbuKFyQLWgxJQyf5QcLLe",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "5000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xc87a06DEE4c0E85912296002617120BBfd5EF990",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "5000",
    "maxTimeoutSeconds": 300
  }
]

{
  "bazaar": {
    "info": {
      "input": {
        "method": "GET",
        "queryParams": {
          "address": "0x098B716B8Aaf21512996dC57EB0615e2383E2f96",
          "chain": "ethereum"
        },
        "type": "http"
      },
      "output": {
        "example": {
          "address": "0x098B716B8Aaf21512996dC57EB0615e2383E2f96",
          "chain": "ethereum",
          "coverage": {
            "malicious_heuristic": "not_checked",
            "total_sdn_addresses": 960
          },
          "matched_label": "ETH",
          "sanctioned": true,
          "sdn_snapshot_at": "2026-07-24T20:02:09Z",
          "signature": "0x…",
          "signed_by": "0x57fF0F084Cba33e6761503f90eEF0Da9F159350c",
          "sources": {
            "ofac_sdn": "ok"
          },
          "verdict": "deny"
        },
        "type": "json"
      }
    },
    "schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "input": {
          "additionalProperties": false,
          "properties": {
            "method": {
              "enum": [
                "GET",
                "HEAD",
                "DELETE"
              ],
              "type": "string"
            },
            "queryParams": {
              "properties": {
                "address": {
                  "description": "Raw blockchain address (EVM 0x-hex, or base58/bech32 for BTC/SOL/TRX/etc.).",
                  "type": "string"
                },
                "chain": {
                  "description": "Chain hint, e.g. ethereum/bitcoin/solana/tron. Advisory — matching is global by address value.",
                  "type": "string"
                }
              },
              "required": [
                "address"
              ],
              "type": "object"
            },
            "type": {
              "const": "http",
              "type": "string"
            }
          },
          "required": [
            "type",
            "method"
          ],
          "type": "object"
        },
        "output": {
          "properties": {
            "example": {
              "properties": {
                "address": {
                  "type": "string"
                },
                "chain": {
                  "type": [
                    "string",
                    "null"
                  ]
                },
                "matched_label": {
                  "type": [
                    "string",
                    "null"
                  ]
                },
                "sanctioned": {
                  "type": "boolean"
                },
                "sdn_snapshot_at": {
                  "type": "string"
                },
                "signature": {
                  "type": "string"
                },
                "signed_by": {
                  "type": "string"
                },
                "verdict": {
                  "enum": [
                    "deny",
                    "clean"
                  ],
                  "type": "string"
                }
              },
              "required": [
                "address",
                "sanctioned",
                "verdict",
                "signed_by",
                "signature"
              ],
              "type": "object"
            },
            "type": {
              "type": "string"
            }
          },
          "required": [
            "type"
          ],
          "type": "object"
        }
      },
      "required": [
        "input"
      ],
      "type": "object"
    }
  }
}

curl "https://sanctions.nsgoods.org/screen"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

const res = await fetch("https://sanctions.nsgoods.org/screen");
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://sanctions.nsgoods.org/screen")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header