Evidence row 750216

What was observed

{
  "endpoints": [
    [
      "x402",
      "https://canary.countersignpay.com/v1/base/head"
    ]
  ],
  "name": "canary.countersignpay.com/v1/base/head",
  "owner_address": "0xa0f3c29f25778ddf46fce2cab5f7e7c25e6a1451",
  "raw": {
    "accepts": [
      {
        "amount": "10000",
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "maxTimeoutSeconds": 300,
        "network": "eip155:8453",
        "payTo": "0xa0f3c29f25778dDf46fce2cAB5f7e7C25E6a1451",
        "scheme": "exact"
      }
    ],
    "description": "Current Base mainnet block height and base fee per gas in wei, read from the chain at request time",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "method": "GET",
            "queryParams": {},
            "type": "http"
          },
          "output": {
            "example": {
              "baseFeePerGas": "1043211",
              "blockHeight": "35812044",
              "network": "eip155:8453",
              "observedAt": "2026-09-15T14:00:00.000Z"
            },
            "type": "json"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "method": {
                  "enum": [
                    "GET"
                  ],
                  "type": "string"
                },
                "queryParams": {
                  "properties": {},
                  "type": "object"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
                "type",
                "method"
              ],
              "type": "object"
            },
            "output": {
              "properties": {
                "example": {
                  "properties": {
                    "baseFeePerGas": {
                      "description": "Base fee per gas of that block, in wei, decimal string",
                      "type": "string"
                    },
                    "blockHeight": {
                      "description": "Latest block number on Base mainnet, decimal string",
                      "type": "string"
                    },
                    "network": {
                      "description": "CAIP-2 chain id, always eip155:8453",
                      "type": "string"
                    },
                    "observedAt": {
                      "description": "ISO 8601 time the chain was read",
                      "type": "string"
                    }
                  },
                  "required": [
                    "blockHeight",
                    "baseFeePerGas",
                    "network",
                    "observedAt"
                  ],
                  "type": "object"
                },
                "type": {
                  "type": "string"
                }
              },
              "required": [
                "type"
              ],
              "type": "object"
            }
          },
          "required": [
            "input"
          ],
          "type": "object"
        }
      }
    },
    "lastUpdated": "2026-10-28T03:51:10.426Z",
    "quality": {
      "l30DaysTotalCalls": 14,
      "l30DaysUniquePayers": 8,
      "lastCalledAt": "2026-10-28T03:51:10.14Z"
    },
    "resource": "https://canary.countersignpay.com/v1/base/head",
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "Current Base mainnet block height and base fee per gas in wei, read from the chain at request time"
}

What the leaf hashes

{"body":"e94e7c7f0df578b42a3bac1893f9d775a4643161a5fa4ae465dec6c8f0696679","id":750216,"kind":"listing","method":"sync.x402_bazaar/1","observed_us":1793178675485065,"prev":525682,"subject":"x402_bazaar:https://canary.countersignpay.com/v1/base/head","subject_kind":"source_record"}

Proof

Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of 2026-10-28 (231336 rows).

1. 0xf85adf106bb75838725501b70ca09ca82d6ed2b211151c99c1c433f614e689f1
2. 0x8796f35d80fa0a66371ffb3f0d176625c37214ac115a76de74583f8a384bfc3d
3. 0xd099f9b12eb111826ddc90771f0fbf5e3ef88476df6b8ebab3f9867f2c7ade5e
4. 0x687fd5a290f580ca7e7c557efeea076a282d13baf9ca7884d51a93577e5800b3
5. 0xd5606cb186a4082b479a44c99b653087f87d8a67e73dfa7157a44c4a099ba254
6. 0x2d45edea2e1352d68fb5e400aa7b9c7343162b4a249b832765e6a6452648abc4
7. 0x9394f358f72b2aed035563dcb2e65aece294a3cf907ca88a9a1a7347415c086f
8. 0x45816b865fdd2706387f604396b7ddca047e38b1974996bdd68effb5f2f2f299
9. 0xc7c13e0367683a16fa55db1ec026cd51da98b9f80edb5d90abc410f10cfac21f
10. 0x1308f37699dde914379153ac60de8e8274fc6161bd68cd543844f31b95e8946f
11. 0x732f8fab98b7b478b7a49424c3365aea972e4296730405422516ea48a96361c6
12. 0xcbaa20f2ab1d4d968c64a80a4776f0f04e0604f96dd36bd268b8820e7228f3de
13. 0xfbe6c6680e81a6a4d0db9bcf0c203bf347d99dfc74bb05632f41c1864103757a
14. 0xb807f07a34f6739a39ed03265a4a5a9c71ac45230c37dc44fd915cc90aa287db
15. 0x33bfb51cb957137510d8a1502cd50241c4c0982e2741290f3b8f2d2b1e69de70
16. 0xef2ebd45f2cfd41dc3eb213cc4cc144c46b7e9ead2de0b9f627463bad16e3ec8
17. 0x67e9ff3e48c515135fcf3df2675aa4996d35d4a328ce41588ee1a7d93347c823
18. 0xe6cfe00ae4e02bc12327e45b5f3334ea5850ba3bcc8e3101d30a8189856a95af

Day root

0x2c19037464cc4c493624565f01775d6446fc78eaa118fc6865bfe2bfca9ff78e

Chained

0xd1d7dee8322ceff8f4c8d83aa1fe4a4466825c2af1c97dbde3d35db61234f7be

Published

On Arc Testnet, block 69584042: 0x8bae2b1d097834c8b458513862d70d29ee807e98dc2e863b27250131c15b35ae