addrbookFor publishers
← The evidence ledger

Evidence row 120121

Observed , by baseline/1.

Kind
listing
About
source_record x402_bazaar:https://saylorinnovations.com/api/kb/ethereum-address-checksum-eip55-wei-usdc-decimals-viem-python
Recorded
Previous row
None: the first of its kind about this subject
Body SHA-256
57c0f65b703207140583769eb21c8093bf48ff475fff55ff7f4aa1398d5de0c4
Leaf
0x9df8a957ea76d039a7ee68aeab734d8f8d87966e036328b4902301fc2d292770

What was observed

{
  "endpoints": [
    [
      "x402",
      "https://saylorinnovations.com/api/kb/ethereum-address-checksum-eip55-wei-usdc-decimals-viem-python"
    ]
  ],
  "name": "Saylor Innovations Guide Library",
  "owner_address": "0xa2a8df0f7caabea4e120a2568118f141569fc8aa",
  "raw": {
    "accepts": [
      {
        "amount": "10000",
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "assetTransferMethod": "eip3009",
          "facilitatorOnly": true,
          "memo": "saylor:ethereum-address-checksum",
          "name": "USD Coin",
          "note": "Base settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
          "version": "2"
        },
        "maxTimeoutSeconds": 120,
        "network": "eip155:8453",
        "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
        "scheme": "exact"
      },
      {
        "amount": "10000",
        "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
        "extra": {
          "assetTransferMethod": "eip3009",
          "facilitatorOnly": true,
          "memo": "saylor:ethereum-address-checksum",
          "name": "USD Coin",
          "note": "Polygon settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
          "version": "2"
        },
        "maxTimeoutSeconds": 120,
        "network": "eip155:137",
        "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
        "scheme": "exact"
      },
      {
        "amount": "10000",
        "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
        "extra": {
          "assetTransferMethod": "eip3009",
          "facilitatorOnly": true,
          "memo": "saylor:ethereum-address-checksum",
          "name": "USD Coin",
          "note": "Arbitrum settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
          "version": "2"
        },
        "maxTimeoutSeconds": 120,
        "network": "eip155:42161",
        "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
        "scheme": "exact"
      },
      {
        "amount": "10000",
        "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
        "extra": {
          "feePayer": "Hc3sdEAsCGQcpgfivywog9uwtk8gUBUZgsxdME1EJy88",
          "memo": "saylor:ethereum-address-checksum",
          "reference": "EBMhufuHe88ec2FfxB48bWhmqxn7RJCZtzSrVakMK2ma",
          "session": "eyJhcnRpY2xlSWQiOiJldGhlcmV1bS1hZGRyZXNzLWNoZWNrc3VtLWVpcDU1LXdlaS11c2RjLWRlY2ltYWxzLXZpZW0tcHl0aG9uIiwicmVmZXJlbmNlIjoiRUJNaHVmdUhlODhlYzJGZnhCNDhiV2htcXhuN1JKQ1p0elNyVmFrTUsybWEiLCJyZWNpcGllbnQiOiI3TFNqZnJKZjhmTnNCOFZBOXU3TjNXRW4yNXNtUUxwb2IzU3Z5VXZYYWN5NyIsIm1pbnQiOiJFUGpGV2RkNUF1ZnFTU3FlTTJxTjF4enliYXBDOEc0d0VHR2tad3lURHQxdiIsIm1pbkFtb3VudCI6MTAwMDAsImV4cCI6MTc5Mjc5ODA3MTE4M30.wdwKV-9EDyflBZzka2oh9WnzvVURZZNOsxhm2LNSTKk"
        },
        "maxTimeoutSeconds": 120,
        "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
        "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
        "scheme": "exact"
      },
      {
        "amount": "10000",
        "asset": "Es9vMFrzaCERmJfrF4H2FYD4KCoNkY11McCe8BenwNYB",
        "extra": {
          "feePayer": "Hc3sdEAsCGQcpgfivywog9uwtk8gUBUZgsxdME1EJy88",
          "memo": "saylor:ethereum-address-checksum",
          "reference": "3r84bLQQwEzU6x2EMQzXVUqGbEVcLCnEDeZVx9ss7NZp",
          "session": "eyJhcnRpY2xlSWQiOiJldGhlcmV1bS1hZGRyZXNzLWNoZWNrc3VtLWVpcDU1LXdlaS11c2RjLWRlY2ltYWxzLXZpZW0tcHl0aG9uIiwicmVmZXJlbmNlIjoiM3I4NGJMUVF3RXpVNngyRU1RelhWVXFHYkVWY0xDbkVEZVpWeDlzczdOWnAiLCJyZWNpcGllbnQiOiI3TFNqZnJKZjhmTnNCOFZBOXU3TjNXRW4yNXNtUUxwb2IzU3Z5VXZYYWN5NyIsIm1pbnQiOiJFczl2TUZyemFDRVJtSmZyRjRIMkZZRDRLQ29Oa1kxMU1jQ2U4QmVud05ZQiIsIm1pbkFtb3VudCI6MTAwMDAsImV4cCI6MTc5Mjc5ODA3MTE4M30.3KfaJYiUqsTYuDWDzTPoJI4JjvBRIvU6Y0K4SApKkH4"
        },
        "maxTimeoutSeconds": 120,
        "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
        "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
        "scheme": "exact"
      },
      {
        "amount": "94522",
        "asset": "So11111111111111111111111111111111111111112",
        "extra": {
          "memo": "saylor:ethereum-address-checksum",
          "native": true,
          "note": "Native SOL: send lamports with a system transfer, not an SPL transfer. Price is quoted live and this quote expires in 120s.",
          "quotedLamports": "97446",
          "reference": "HCgqsRyDnu4NyNEcVP8bYBrzhn6DYukSfa5kEfHLT4Vc",
          "session": "eyJhcnRpY2xlSWQiOiJldGhlcmV1bS1hZGRyZXNzLWNoZWNrc3VtLWVpcDU1LXdlaS11c2RjLWRlY2ltYWxzLXZpZW0tcHl0aG9uIiwicmVmZXJlbmNlIjoiSENncXNSeURudTROeU5FY1ZQOGJZQnJ6aG42RFl1a1NmYTVrRWZITFQ0VmMiLCJyZWNpcGllbnQiOiI3TFNqZnJKZjhmTnNCOFZBOXU3TjNXRW4yNXNtUUxwb2IzU3Z5VXZYYWN5NyIsIm1pbnQiOm51bGwsIm1pbkFtb3VudCI6OTQ1MjIsImV4cCI6MTc5Mjc5ODA3MTE4M30.9WvnqXywhgJUdZxEEi3v0r3SnDmaTp3QjcE-9AZtS54",
          "solUsdPrice": 102.62
        },
        "maxTimeoutSeconds": 120,
        "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
        "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
        "scheme": "exact"
      }
    ],
    "description": "Ethereum address and amount safety - EIP-55 checksum, isAddress strict vs getAddress normalizing, parseUnits rounding, float vs Decimal USDC",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "method": "GET",
            "type": "http"
          },
          "output": {
            "example": {
              "body": "Executed with eth-utils (Python) and viem (JS): is_checksum_address versus is_address, a one-character change, missing 0x, parseUnits(1.2345678, 6) rounding to 1234568, formatUnits, to_wei, Decimal versus float for 0.29 and 0.1, and Number precision above 2^53.",
              "c": "Self-Hosting & Infra",
              "id": "ethereum-address-checksum-eip55-wei-usdc-decimals-viem-python",
              "t": "Ethereum Addresses and Token Amounts: EIP-55 Checksums, isAddress vs getAddress, parseUnits Rounding and Float Traps"
            },
            "type": "json"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "method": {
                  "enum": [
                    "GET"
                  ],
                  "type": "string"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
                "type",
                "method"
              ],
              "type": "object"
            },
            "output": {
              "properties": {
                "example": {
                  "properties": {
                    "body": {
                      "description": "Main body text",
                      "type": "string"
                    },
                    "c": {
                      "description": "Category of the guide",
                      "type": "string"
                    },
                    "id": {
                      "description": "Identifier of the record",
                      "type": "string"
                    },
                    "license": {
                      "description": "License identifier",
                      "type": "string"
                    },
                    "price": {
                      "description": "Price",
                      "type": [
                        "number",
                        "null"
                      ]
                    },
                    "t": {
                      "description": "Title of the guide",
                      "type": "string"
                    }
                  },
                  "required": [
                    "id",
                    "t",
                    "c",
                    "body"
                  ],
                  "type": "object"
                },
                "type": {
                  "const": "json",
                  "type": "string"
                }
              },
              "required": [
                "type"
              ],
              "type": "object"
            }
          },
          "required": [
            "input"
          ],
          "type": "object"
        }
      }
    },
    "iconUrl": "https://res.cloudinary.com/bdb-prod/image/upload/c_fill,ar_1:1,w_256,h_256,f_auto,q_auto/v1791811517/bazaar-icons/bc5e2b3d111ebbef.jpg",
    "lastUpdated": "2026-10-23T23:25:51.232Z",
    "quality": {
      "l30DaysTotalCalls": 2,
      "l30DaysUniquePayers": 2,
      "lastCalledAt": "2026-10-23T23:25:50.993Z"
    },
    "resource": "https://saylorinnovations.com/api/kb/ethereum-address-checksum-eip55-wei-usdc-decimals-viem-python",
    "serviceName": "Saylor Innovations Guide Library",
    "tags": [
      "ethereum",
      "eip-55",
      "viem",
      "usdc",
      "web3"
    ],
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "Ethereum address and amount safety - EIP-55 checksum, isAddress strict vs getAddress normalizing, parseUnits rounding, float vs Decimal USDC"
}

What the leaf hashes

{"body":"57c0f65b703207140583769eb21c8093bf48ff475fff55ff7f4aa1398d5de0c4","id":120121,"kind":"listing","method":"baseline/1","observed_us":1793025617383497,"prev":null,"subject":"x402_bazaar:https://saylorinnovations.com/api/kb/ethereum-address-checksum-eip55-wei-usdc-decimals-viem-python","subject_kind":"source_record"}

Proof

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

  1. 0x9df84a155aa91ef194db95b870eee9b7380ad3959979d639c2e23e083bde8aa4
  2. 0xbb707e35765346e102f5ff99e8c1f5d18d5c68bf4547e6535774f3393041ad06
  3. 0xb08f7a7fbed2b85bc69c58514ebac31b6fb59ddea57d8e41a7e4d1d3a240175b
  4. 0xbc9cb96bed16be81d636c1695d94dca27d16f88de36dba6f08c1fc5eb27c264c
  5. 0x38635864c4ce992743a3064fd0c99be0296dd182b6fc4076e17ce2cc3f4b07b3
  6. 0xaefb50edbf773e172aed079a1cbfadba2c963d4b2e05606327273318e5fe17c7
  7. 0xb63cf205252e23ad36ae3e0e07fc47a43e12ece2015631a9529791474184be24
  8. 0x7bfd405c6fefed64ea1296cd04281dd7f008d90ca6acfee880715cf6c96e745e
  9. 0x49c14533a12c09ed4a3ff0275a70f2680d5bbb359844fe1808c7b11e12e87d18
  10. 0xdbcb6bb00700465648e25b93c41af8658c581916f65193d2b15aedd3a021f631
  11. 0x351390dbbaa59bf254610c44de6ad39906ad2c226e8f737f7d774c0b9d382abf
  12. 0x73cca5e5ba14c0aaa799d5324b89eb846e3c5546aab3b2cda0c05c5eeaa03168
  13. 0x99a4e0f8b23989f58b564c1b6e419578b4388f6e0dbf6e50177c1bd476302d0e
  14. 0x6713795704ddd9c528d421fadd9cc96b0200a4ddbba84f88e718d4968dde888b
  15. 0x62a900133713919f4eed33d8336876b7a6d538233b8a4f3ed03b29aa44f5bad0
  16. 0x1ac20d30773e1f4f2f811540e9a99b5cca9177c9e2e029acc0d80cf3f1d11f0f
  17. 0xd21942ae3214eff88e08ab04884fd4b11958b51af9a0741b7668e2d07a2c56c9
  18. 0x9a9024edb5069d88a324facb310a5ce8e495214bbaa968f077bede437390194f
  19. 0x9b9ce5b74b9bab5121612ef6b64920a8d453cbf311096a423eef9702747e868a
Day root
0xf43e8dcc3d451a4788b26be904c55e8c4c0fa75c9666796c51db38d37e2c0df8
Chained
0x702d5ac508f08b0d1accf36af25822d8e5660367494edd17a642fb61e158a57a
Published
On Arc Testnet, block 69251483: 0x495162f8936e19f0039918feebe6c307f327cd6bf8c37219620b1970041fa9ae

How to check it · This row as JSON