Evidence row 261231

What was observed

{
  "endpoints": [
    [
      "x402",
      "https://offercheck.offercheck.workers.dev/v1/fx"
    ]
  ],
  "name": "offercheck",
  "owner_address": "0xb9721fdd2ec85f7f604f5bbca2292d7c4ff6b62c",
  "raw": {
    "accepts": [
      {
        "amount": "2000",
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "maxTimeoutSeconds": 120,
        "network": "eip155:8453",
        "payTo": "0xB9721FDD2EC85F7f604F5BBcA2292d7C4ff6B62c",
        "scheme": "exact"
      }
    ],
    "description": "Convert between 30 major currencies (USD, EUR, GBP, JPY, CHF, CNY, INR, ILS, AUD, CAD, ...) using the European Central Bank's daily reference rates: rate and converted amount for one or many target currencies, optional historical date back to 1999. Returns the ECB rate date and source. $0.002 per call.",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "method": "GET",
            "queryParams": {
              "amount": "100",
              "from": "USD",
              "to": "EUR,GBP"
            },
            "type": "http"
          },
          "output": {
            "example": {
              "amount": 100,
              "date": "2026-09-25",
              "fetched_at": "2026-09-25T20:00:00.000Z",
              "from": "USD",
              "ms": 95,
              "rates": {
                "EUR": {
                  "converted": 87.696,
                  "rate": 0.87696
                },
                "GBP": {
                  "converted": 75.458,
                  "rate": 0.75458
                }
              },
              "source": "European Central Bank euro foreign exchange reference rates (published once per business day ~16:00 CET) via frankfurter.dev; non-EUR pairs are cross rates through EUR",
              "warnings": []
            },
            "type": "json"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "method": {
                  "enum": [
                    "GET"
                  ],
                  "type": "string"
                },
                "queryParams": {
                  "properties": {
                    "amount": {
                      "default": "1",
                      "description": "Amount in the base currency to convert, as a decimal number string, e.g. \"100\" (default 1). Query parameters are strings, so the Coinbase Bazaar validator rejects a numeric type here.",
                      "pattern": "^[0-9]+(\\.[0-9]+)?$",
                      "type": "string"
                    },
                    "date": {
                      "description": "Optional historical date YYYY-MM-DD (ECB business days from 1999-01-04); omit for the latest rates",
                      "type": "string"
                    },
                    "from": {
                      "default": "USD",
                      "description": "Base currency, ISO 4217 code (default USD)",
                      "type": "string"
                    },
                    "to": {
                      "default": "EUR",
                      "description": "Target currency or comma-separated list (default EUR); any of the 30 ECB currencies",
                      "type": "string"
                    }
                  },
                  "required": [],
                  "type": "object"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
                "type",
                "method"
              ],
              "type": "object"
            },
            "output": {
              "properties": {
                "example": {
                  "type": "object"
                },
                "type": {
                  "type": "string"
                }
              },
              "required": [
                "type"
              ],
              "type": "object"
            }
          },
          "required": [
            "input"
          ],
          "type": "object"
        }
      }
    },
    "lastUpdated": "2026-10-26T15:58:01.07Z",
    "quality": {
      "l30DaysTotalCalls": 10,
      "l30DaysUniquePayers": 6,
      "lastCalledAt": "2026-10-26T00:16:22.508Z"
    },
    "resource": "https://offercheck.offercheck.workers.dev/v1/fx",
    "serviceName": "offercheck",
    "tags": [
      "finance",
      "fx",
      "exchange-rate",
      "currency",
      "crypto"
    ],
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "Convert between 30 major currencies (USD, EUR, GBP, JPY, CHF, CNY, INR, ILS, AUD, CAD, ...) using the European Central Bank's daily reference rates: rate and converted amount for one or many target currencies, optional historical date back to 1999. Returns the ECB rate date and source. $0.002 per call."
}

What the leaf hashes

{"body":"ad549a62a45ce713d4bd1cbc6d79df53ee59f5616418f645b91374da9c5f47c2","id":261231,"kind":"listing","method":"sync.x402_bazaar/1","observed_us":1793032170128130,"prev":1246,"subject":"x402_bazaar:https://offercheck.offercheck.workers.dev/v1/fx","subject_kind":"source_record"}

Proof

Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of 2026-10-26 (296695 rows).

1. 0x81603a81931639b36176cf7bd38f3de8b42581a5572e17270f7e350327280005
2. 0x60e1dd5a3d1e1c58003d17e785a990fa6e60541965a41cb7fc0eea4f3952551a
3. 0x7c258ae8e7d58c436d4898eb9f436d072fa3df8ad95ce98b142a274e8e977c6d
4. 0x18d3127a1596b82196b09babca2a4beff28601147a86c2fc1f90c6e1e706987b
5. 0xb4a09e2eaaf32315479c85624d31a8596d4d7df5adea8370bacba3c03f357fb4
6. 0xb4455a6d8d3ea641515771c645093b604d322d57f72e5e23dd461cb45ac6020e
7. 0xf914f9c01330616abcd2292824df95476775829d46e775647682ef93e5ff98ba
8. 0x5bd10b1678274b52216485c55f5f1686074201d309f96f604854ac8be508b4b2
9. 0x0663d749810a359fb0c24bc646f7a866c267732ce10aaf675e4f9ec2d95e520f
10. 0xa6bf3e233d964bf47c35e307fb1e82a9db46b720ed0d1a887fab65896dbfda9a
11. 0xb998e012b473bde18346485cd0b7b8b31ab48d5f22ba9bc660bb2e523161e255
12. 0x08155d70132f82e370214fc5b72194dfa6f5e57670b7bcf74776e8418302897e
13. 0x4d2ee986a690e903126f449b4e9e62d5572b350357ab4496a83488949b131c29
14. 0x0eff463856b0992d53ab7d8c0b97c71541413358bdd445710c1e4b6aeb4d8f78
15. 0x7eb603d37f0f22dae1ea013e391889906ffc0139ff26e25b044bee38eec8f9b2
16. 0x2b6e23e3624a1b66e1d2298cfbce99a93ce6b13d24a58112a71802d79c5f7a76
17. 0xd21942ae3214eff88e08ab04884fd4b11958b51af9a0741b7668e2d07a2c56c9
18. 0x9a9024edb5069d88a324facb310a5ce8e495214bbaa968f077bede437390194f
19. 0x9b9ce5b74b9bab5121612ef6b64920a8d453cbf311096a423eef9702747e868a

Day root

0xf43e8dcc3d451a4788b26be904c55e8c4c0fa75c9666796c51db38d37e2c0df8

Chained

0x702d5ac508f08b0d1accf36af25822d8e5660367494edd17a642fb61e158a57a

Published

On Arc Testnet, block 69251483: 0x495162f8936e19f0039918feebe6c307f327cd6bf8c37219620b1970041fa9ae