Give this API any text or binary data and it returns its fingerprint under whichever hash

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xE9740820225B3918b4ddd1292C7cA4Ca0e2C2F08",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "10000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "payTo": "8ugAWAXDB8V18kiUrGZTq1oMvU3C6Fxs8hfC6rvzQT3b",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "10000",
    "maxTimeoutSeconds": 300
  }
]

{
  "bazaar": {
    "info": {
      "input": {
        "body": {
          "algorithms": [
            "sha256",
            "sha512",
            "crc32"
          ],
          "hmac": {
            "algorithm": "sha256",
            "expected_signature": "edddd7a6a42a411ab35b993d690cc7bd5d3be3d9262f66fef16ac2be10e0539a",
            "key": "whsec_test_secret_key_123",
            "mode": "verify"
          },
          "input": "{\"order_id\":\"A-1029\",\"amount\":4200}",
          "input_encoding": "utf-8",
          "output_encoding": "hex"
        },
        "bodyType": "json",
        "method": "POST",
        "type": "http"
      },
      "output": {
        "example": {
          "api_version": "1.0.0",
          "digests": {
            "crc32": "74c679bb",
            "sha256": "aa27c1f5aeb13292cb74153461b1eb3193efe4501c109a99103d304657798cf6",
            "sha512": "f9b133b06a4b7309392429f15108af870c073288f4297b85dba0ebb907f26c71a808abbe1d197f67ad4b7a1ab83507b1ac1774aa0a4295919e7b9697b395be07"
          },
          "hmac": {
            "algorithm": "sha256",
            "computed_signature": "edddd7a6a42a411ab35b993d690cc7bd5d3be3d9262f66fef16ac2be10e0539a",
            "matches": true,
            "mode": "verify"
          },
          "input_bytes": 35
        },
        "type": "json"
      }
    },
    "schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "input": {
          "additionalProperties": false,
          "properties": {
            "body": {
              "additionalProperties": false,
              "properties": {
                "algorithms": {
                  "description": "Which fingerprint methods to use. Choose any of: md5, sha1, sha224, sha256, sha384, sha512, sha3_256, sha3_512, blake2b, blake2s, crc32, adler32. You may list several at once.",
                  "type": "array"
                },
                "hmac": {
                  "description": "Optional. Include this block to sign data or verify a signature. Contains: mode ('sign' or 'verify'), algorithm (md5, sha1, sha256, or sha512), key (your full secret key as a string), and expected_signature (only needed when mode is 'verify').",
                  "type": "object"
                },
                "input": {
                  "description": "The text or data you want to hash. For binary data, base64-encode it first and set input_encoding to 'base64'.",
                  "type": "string"
                },
                "input_encoding": {
                  "description": "How the input is encoded. Use 'utf-8' for normal text (default) or 'base64' for binary data.",
                  "type": "string"
                },
                "output_encoding": {
                  "description": "How to display the resulting fingerprints. Choose 'hex' (default, lowercase letters and numbers), 'base64', or 'base64url' (safe for URLs).",
                  "type": "string"
                }
              },
              "required": [
                "input",
                "algorithms"
              ],
              "type": "object"
            },
            "bodyType": {
              "enum": [
                "json",
                "form-data",
                "text"
              ],
              "type": "string"
            },
            "method": {
              "enum": [
                "POST",
                "PUT",
                "PATCH"
              ],
              "type": "string"
            },
            "type": {
              "const": "http",
              "type": "string"
            }
          },
          "required": [
            "type",
            "method",
            "bodyType",
            "body"
          ],
          "type": "object"
        },
        "output": {
          "properties": {
            "example": {
              "properties": {
                "api_version": {
                  "type": "string"
                },
                "digests": {
                  "additionalProperties": true,
                  "type": "object"
                },
                "hmac": {
                  "additionalProperties": true,
                  "type": "object"
                },
                "input_bytes": {
                  "type": "integer"
                }
              },
              "required": [
                "api_version",
                "input_bytes",
                "digests",
                "hmac"
              ],
              "type": "object"
            },
            "type": {
              "type": "string"
            }
          },
          "required": [
            "type"
          ],
          "type": "object"
        }
      },
      "required": [
        "input"
      ],
      "type": "object"
    }
  }
}

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

const res = await fetch("https://hash-hmac.underscoredone.com/hash");
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://hash-hmac.underscoredone.com/hash")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header