Evidence row 547738

What was observed

{
  "endpoints": [
    [
      "x402",
      "https://ask.singitai.app/v1/exa/answer"
    ]
  ],
  "name": "SingIt Web Answers (Exa)",
  "owner_address": "0xc23d1dc0f5fce1abffb051e06cb93f0329968b4e",
  "raw": {
    "accepts": [
      {
        "amount": "7500",
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "maxTimeoutSeconds": 120,
        "network": "eip155:8453",
        "payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
        "scheme": "exact"
      },
      {
        "amount": "8500",
        "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
        "extra": {
          "feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
        },
        "maxTimeoutSeconds": 120,
        "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
        "payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
        "scheme": "exact"
      }
    ],
    "description": "Web answers with citations from Exa: a cited answer to a question. Call it when an agent needs a sourced answer rather than raw search results, with no API key or account. Served by SingIt.",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "body": {
              "query": "What is x402?"
            },
            "bodyType": "json",
            "method": "POST",
            "type": "http"
          },
          "output": {
            "example": {
              "answer": "x402 is an open standard for paying for an API call with a stablecoin over HTTP 402.",
              "billing": {
                "currency": "USDC",
                "exaAtomic": "5000",
                "feeAtomic": "1000",
                "markupAtomic": "1500",
                "totalAtomic": "7500"
              },
              "citations": [
                {
                  "id": "https://x402.org",
                  "title": "x402",
                  "url": "https://x402.org"
                }
              ]
            },
            "type": "json"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "body": {
                  "properties": {
                    "model": {
                      "enum": [
                        "exa",
                        "exa-fast"
                      ],
                      "type": "string"
                    },
                    "query": {
                      "description": "The question to answer with citations.",
                      "maxLength": 2000,
                      "minLength": 1,
                      "type": "string"
                    },
                    "systemPrompt": {
                      "description": "Guidance for the answer's style.",
                      "type": "string"
                    },
                    "text": {
                      "description": "Include the text of the cited pages.",
                      "type": "boolean"
                    },
                    "userLocation": {
                      "description": "Two-letter country code.",
                      "type": "string"
                    }
                  },
                  "required": [
                    "query"
                  ]
                },
                "bodyType": {
                  "enum": [
                    "json",
                    "form-data",
                    "text"
                  ],
                  "type": "string"
                },
                "method": {
                  "enum": [
                    "POST"
                  ],
                  "type": "string"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
                "type",
                "method",
                "bodyType",
                "body"
              ],
              "type": "object"
            },
            "output": {
              "properties": {
                "example": {
                  "properties": {
                    "billing": {
                      "description": "What was charged, in USDC micro-units",
                      "properties": {
                        "currency": {
                          "const": "USDC",
                          "type": "string"
                        },
                        "exaAtomic": {
                          "type": "string"
                        },
                        "feeAtomic": {
                          "type": "string"
                        },
                        "markupAtomic": {
                          "type": "string"
                        },
                        "totalAtomic": {
                          "description": "The amount settled",
                          "type": "string"
                        }
                      },
                      "type": "object"
                    }
                  },
                  "required": [
                    "billing"
                  ],
                  "type": "object"
                },
                "type": {
                  "type": "string"
                }
              },
              "required": [
                "type"
              ],
              "type": "object"
            }
          },
          "required": [
            "input"
          ],
          "type": "object"
        }
      },
      "builder-code": {
        "info": {
          "a": "bc_is3fuv36"
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "additionalProperties": false,
          "properties": {
            "a": {
              "description": "App builder code",
              "pattern": "^[a-z0-9_]{1,32}$",
              "type": "string"
            },
            "s": {
              "description": "Service builder codes",
              "items": {
                "pattern": "^[a-z0-9_]{1,32}$",
                "type": "string"
              },
              "maxItems": 11,
              "type": "array"
            },
            "w": {
              "description": "Wallet builder code",
              "pattern": "^[a-z0-9_]{1,32}$",
              "type": "string"
            }
          },
          "type": "object"
        }
      }
    },
    "iconUrl": "https://res.cloudinary.com/bdb-prod/image/upload/c_fill,ar_1:1,w_256,h_256,f_auto,q_auto/v1792921332/bazaar-icons/a240c598b3f928d1.png",
    "lastUpdated": "2026-10-27T16:48:51.923Z",
    "quality": {
      "l30DaysTotalCalls": 6,
      "l30DaysUniquePayers": 5,
      "lastCalledAt": "2026-10-27T16:48:51.588Z"
    },
    "resource": "https://ask.singitai.app/v1/exa/answer",
    "serviceName": "SingIt Web Answers (Exa)",
    "tags": [
      "web-search",
      "answers",
      "citations",
      "exa",
      "search"
    ],
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "Web answers with citations from Exa: a cited answer to a question. Call it when an agent needs a sourced answer rather than raw search results, with no API key or account. Served by SingIt."
}

What the leaf hashes

{"body":"1c087c2eb5d86a95ed41f8f831612343feed55d037d9e425a1bed0e284beea3c","id":547738,"kind":"listing","method":"sync.x402_bazaar/1","observed_us":1793133215297268,"prev":526615,"subject":"x402_bazaar:https://ask.singitai.app/v1/exa/answer","subject_kind":"source_record"}

Proof

Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of 2026-10-27 (273461 rows).

1. 0x770d39bd55981454b27442b3c6b408cf4d7f1dfb117739f2f7916949e6fe9481
2. 0x3913c2f65ed7ab8d6590b318df5a71816a71e01de5448d0cec17bb7182da84bb
3. 0xd7b57d5693557693b15a731c6dc999a34a9f63ce2ab6f1da88425f51eda74c89
4. 0x515849f51cc95cc5a8e6e3e5fc24626ca37fbaff9577fbd881fa42c2d77d8b96
5. 0x35f0caab98d6de08d61d4bb765dc6cb81cf9c23e925579d19ab6077d234684a7
6. 0xb2d67d75e5630dbdde6f634799c7400f1c4ad12ff27b6416ebcf70692a8b97f8
7. 0xc91d3d21eabd947d6d1c94dda34bffdc8e8fad4c258a85d5b8fb548e724af44f
8. 0x68d501b4a9b8404ea727e74f98e8c742bfc7889eea566860802945e2d6e5ebb8
9. 0x9d40c0a0515c66c047279229eed5cfed41bb12e59a75b1b9a816e7489787e69a
10. 0x0dcbf51fb2ecee58e0aec94fcb361cef89d57ae5d6a06d812d391867385ddd8e
11. 0xe6bb1ce9f4488db1a61582719cb796889efd3c003080931b82d2a8a465d0fec2
12. 0x6834d22f4558c2279e3de3027a40f72cd350b3c4a2e54be57aff9ec2c9eaf01a
13. 0x4094bd5bc2ab60e4518d1ee8a13455a69d7484ea62ecdca2618d0f39d3403503
14. 0x9848c068b1371232529d2b5738fdc45b854c57da041b69ea7c9e112b14e2d9d1
15. 0x275720ecabb68df33eee92ae4fd70572a8d952d6c61c061c2869cfc3217aa5c5
16. 0x23cf9bb4337ee8be7fcae368fd69d24c62c11fb45882127b4cd919bb96a19996
17. 0x0e01aa9525097570a6edaf32bfc959de57bf5c24317cf10c0716affea85ca60d
18. 0xa20d48798a34aba12eb9c7297722982d910f06c148f5e27ac59307422964a585
19. 0x9fc354c0ea3efc3f1b6548bb77ea902a50f2c9647647ea61592efce2bd795699

Day root

0xdd77e5e99da32c3f154180d63e3c3e6fe11e896a2c6896412ef6b5c4bcf7e795

Chained

0x23bb4dfd09f55c15ac3962f53578e02c6114d5bfd9bb451cf8794fb6e2817ef4

Published

On Arc Testnet, block 69414147: 0xb2ebd83aafeb765a0ce66e76aefb133ed06606c98038fd56191e2bcd1dcb77b4