Evidence row 541570

What was observed

{
  "count": 7,
  "tools": [
    {
      "description": "Check if a URL is reachable before paying to read it. HEAD request following up to five redirects: status code, final URL, content-type, content-length and last-modified — no page body fetched or charged for content. Use before read_url_as_markdown ($0.003) to confirm a URL resolves and is HTML before paying the bigger fee for extraction. Doesn't check robots.txt (that's enforced on the actual read). Some servers reject HEAD (405/403) even though GET works, so a non-2xx here doesn't guarantee read_url_as_markdown will also fail. Costs $0.001 USDC per call (x402).",
      "inputSchema": {
        "$schema": "http://json-schema.org/draft-07/schema#",
        "additionalProperties": false,
        "properties": {
          "url": {
            "description": "Public http(s) URL to check",
            "format": "uri",
            "type": "string"
          }
        },
        "required": [
          "url"
        ],
        "type": "object"
      },
      "name": "check_url_status"
    },
    {
      "description": "Where is it cheapest to send this transaction right now?. Ranks all 6 supported chains (Base, Ethereum, Arbitrum, Optimism, Polygon, Solana) by USD cost for a transaction type (transfer, USDC transfer or swap) at a speed tier (slow/standard/fast). Returns the ranking, the cheapest chain, and any chains queried in parallel that didn't respond (in failed[]). Costs $0.005 USDC per call (x402).",
      "inputSchema": {
        "$schema": "http://json-schema.org/draft-07/schema#",
        "additionalProperties": false,
        "properties": {
          "tier": {
            "default": "standard",
            "description": "Speed tier",
            "enum": [
              "slow",
              "standard",
              "fast"
            ],
            "type": "string"
          },
          "tx": {
            "default": "transfer",
            "description": "Transaction type",
            "enum": [
              "transfer",
              "usdc_transfer",
              "swap"
            ],
            "type": "string"
          }
        },
        "type": "object"
      },
      "name": "compare_gas_costs"
    },
    {
      "description": "USD cost of a custom gas limit or compute-unit budget. Prices an arbitrary transaction, not just the 3 canned types get_gas_price/compare_gas_costs cover: pass your own gas limit (EVM chains) or compute-unit budget (Solana) and get its USD cost at a speed tier. Use this for a contract call, NFT mint or any tx whose gas usage you already know or estimated via eth_estimateGas/simulation — get_gas_price's 3 canned tx types won't fit it. Typical EVM units: 21,000 plain transfer, 50,000-65,000 ERC20 transfer, 100,000-250,000 typical contract call/NFT mint, 150,000-400,000 DEX swap; typical Solana compute units: 200,000 simple transfer, up to 1,400,000 (the per-tx cap) for a complex instruction. Excludes OP-stack L1 data fee (depends on calldata size, not gas limit) — add a few % for Base/Optimism to be safe. Costs $0.002 USDC per call (x402).",
      "inputSchema": {
        "$schema": "http://json-schema.org/draft-07/schema#",
        "additionalProperties": false,
        "properties": {
          "chain": {
            "description": "Chain to query",
            "enum": [
              "base",
              "ethereum",
              "arbitrum",
              "optimism",
              "polygon",
              "solana"
            ],
            "type": "string"
          },
          "tier": {
            "default": "standard",
            "description": "Speed tier",
            "enum": [
              "slow",
              "standard",
              "fast"
            ],
            "type": "string"
          },
          "units": {
            "description": "Gas limit (EVM) or compute units (Solana)",
            "exclusiveMinimum": 0,
            "type": "integer"
          }
        },
        "required": [
          "chain",
          "units"
        ],
        "type": "object"
      },
      "name": "estimate_custom_tx_cost"
    },
    {
      "description": "Current gas/fee tiers and USD costs for one chain. Slow/standard/fast gas tiers and USD cost of a transfer, USDC transfer and swap, for Base, Ethereum, Arbitrum, Optimism, Polygon or Solana. Updated every 15s. Solana is compute-unit pricing, not gwei-style gas; the other 5 are EVM. Use for one chain's prices; use compare_gas_costs to rank all 6, or estimate_custom_tx_cost for a gas limit/compute budget outside the 3 canned tx types here. x402: 402 first, retry with PAYMENT-SIGNATURE (MCP: _meta[\"x402/payment\"]) — unpaid/failed calls are never charged. Costs $0.002 USDC per call (x402).",
      "inputSchema": {
        "$schema": "http://json-schema.org/draft-07/schema#",
        "additionalProperties": false,
        "properties": {
          "chain": {
            "description": "Chain to query",
            "enum": [
              "base",
              "ethereum",
              "arbitrum",
              "optimism",
              "polygon",
              "solana"
            ],
            "type": "string"
          }
        },
        "required": [
          "chain"
        ],
        "type": "object"
      },
      "name": "get_gas_price"
    },
    {
      "description": "USD price of a chain's native token, no gas data. Just the native-token USD price (ETH, POL or SOL), sourced from MEXC/Gate.io/Coinbase with the same price feed get_gas_price uses. Use this when you only need the asset price, not fees — get_gas_price and compare_gas_costs already return nativeUsd alongside gas data, so call this instead only to skip the gas lookup (e.g. valuing a wallet balance, not estimating a transaction). Costs $0.001 USDC per call (x402).",
      "inputSchema": {
        "$schema": "http://json-schema.org/draft-07/schema#",
        "additionalProperties": false,
        "properties": {
          "chain": {
            "description": "Chain to query",
            "enum": [
              "base",
              "ethereum",
              "arbitrum",
              "optimism",
              "polygon",
              "solana"
            ],
            "type": "string"
          }
        },
        "required": [
          "chain"
        ],
        "type": "object"
      },
      "name": "get_native_token_price"
    },
    {
      "description": "List supported chains (Base, Ethereum, Arbitrum, Optimism, Polygon, Solana) and the gas-unit constants used by the paid tools (free). Always returns the full, unfiltered list of all 6 chains (no input/filter params). gasUnits.{transfer|usdc_transfer|swap} are plain integers: the gas units a typical transaction of that type costs on an EVM chain (evm) or in Solana compute units (svm) — multiply by the chain's current fee from get_gas_price to estimate USD cost yourself, or just call get_gas_price/compare_gas_costs which already does this.",
      "inputSchema": {
        "$schema": "http://json-schema.org/draft-07/schema#",
        "properties": {},
        "type": "object"
      },
      "name": "list_chains"
    },
    {
      "description": "Convert any web page into clean, readable Markdown. Fetches a public web page and returns clean Markdown: title, byline, site name, excerpt, word count and article body. Respects robots.txt, blocks private hosts, follows up to five redirects, caps the page at 3 MB. links=true adds outbound links. Not charged on failure: 403 if robots.txt disallows the path, 415 for non-HTML, 422 if no article text extracts, 502 on upstream error. Costs $0.003 USDC per call (x402).",
      "inputSchema": {
        "$schema": "http://json-schema.org/draft-07/schema#",
        "additionalProperties": false,
        "properties": {
          "links": {
            "default": false,
            "description": "Include outbound links (max 200)",
            "type": "boolean"
          },
          "url": {
            "description": "Public http(s) URL to read",
            "format": "uri",
            "type": "string"
          }
        },
        "required": [
          "url"
        ],
        "type": "object"
      },
      "name": "read_url_as_markdown"
    }
  ]
}

What the leaf hashes

{"body":"eecbb8625416ee6c39106cf11e5e605d4373089f5114b1e725ff048f08f36fe9","id":541570,"kind":"mcp.tools","method":"probe.mcp/1","observed_us":1793130450214780,"prev":null,"subject":"26e56d7c-78a7-4459-a38e-c46655cb569f","subject_kind":"endpoint"}

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. 0xa221a32491439dc8acddf7e811fc5db52c36a887284d9fa3c67d49679917f08c
2. 0xff6262743187676c4df9289b95e150d8705f4fe5ef9c760f534dd741c67a2bd3
3. 0xcb8b1b9b21b87b94ef472fafed0607efbe0424d9e5d9f3fe5eeef5be7fa21c9b
4. 0x1cb98f5c7794d8bd36c572105edaa04f9f1bb85bb8d3fdd8e5a4cd2e4afcb2d3
5. 0x6d44709f4f6622810eae7f1555fc3518f711efea72dcd47d28f70ba5d0fdff2d
6. 0x8829a8e914f489e27ef906bc58563f266a522e2082694a4aefc1b258dde6562a
7. 0x5b7f0f1466a5cf1bad6cc5e26154051f056b421e2e85790f7d983905dd26f9c8
8. 0x296e3ffeb89e171f6fa16a0899a9ea846a3d1dceb2d08054ce241c4ce046c722
9. 0xac3fcf77005c23a2407b2fa646f7146cbd44ed57ac48e9f57e7eebbcadee2927
10. 0xc2407975175c710b5f8a7ee92f90c566f70f556badcec899706506405298d3d1
11. 0x60256611194f4b2e6a37447763b0aac23cbea6f8ca40ee0b8fbe44b2119b441f
12. 0x0c9efc71bd73a056aab018d34b600797c2287eaa0df0398c8404046e9420d684
13. 0x87816aee66e8f6e0f1e55ea83733bb58cf9612d36c45fd5b7fc5d6f4484b78fd
14. 0x0644f7e2a4b5bf9b66f185cc3fbb766d456ad94490183852f4c6db5855114cc5
15. 0xa3fff4662cd48659f5bafd0612931759a90e53a7b4209ed8f26f6594a07bb547
16. 0x64c405a28e8819716221eb2529fe4ce277ab08025e17e685cbd5ece75ceb75c7
17. 0xf30fddbf4811226c58e8f0daf36fddd79fc5f1356b592bb1d99a8061ddbabe66
18. 0x2bf8151e5f157dd183b9de6fa00469551932a7a6e3f33a694895000ac9061197
19. 0x9fc354c0ea3efc3f1b6548bb77ea902a50f2c9647647ea61592efce2bd795699

Day root

0xdd77e5e99da32c3f154180d63e3c3e6fe11e896a2c6896412ef6b5c4bcf7e795

Chained

0x23bb4dfd09f55c15ac3962f53578e02c6114d5bfd9bb451cf8794fb6e2817ef4

Published

On Arc Testnet, block 69414147: 0xb2ebd83aafeb765a0ce66e76aefb133ed06606c98038fd56191e2bcd1dcb77b4