MCPFax On-Chain Toolkit

The on-chain facts you need in the seconds before you transact.

CommunityDegradedNo sign-inGlobalFreeRead-only

What it can do

    What data it sees

    Do you need an account

    No: the server works without sign-in

    The on-chain facts you need in the seconds before you transact.

    How to connect

    How to connect MCPFax On-Chain Toolkit to Claude

    The server address to paste into Claude settings:

    https://onchain-toolkit.bowling-anthony.workers.dev/mcp

    1. Open Claude (claude.ai or the desktop app).
    2. Go to Settings → Connectors.
    3. Click Add custom connector.
    4. Paste the server address copied below into Remote MCP server URL and click Add.
    5. In a chat, click + → Connectors and switch the new connector on.

    Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

    Authorization

    After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

    How to connect MCPFax On-Chain Toolkit to ChatGPT

    The server address to paste into ChatGPT settings:

    https://onchain-toolkit.bowling-anthony.workers.dev/mcp

    1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
    2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
    3. Open Settings → Connectors and click Create.
    4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
    5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
    6. In a new chat open + → Apps/Connectors and enable the connector.

    OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

    Authorization

    On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

    How to connect MCPFax On-Chain Toolkit to Cursor

    The server address to paste into Cursor settings:

    https://onchain-toolkit.bowling-anthony.workers.dev/mcp

    Fastest: click Open in Cursor below and confirm the prompt.

    Manually:

    1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
    2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
    3. Save the file. The server appears in the MCP list; authorize it there if asked.

    Authorization

    If the service needs sign-in, an authorize button appears next to the server in the MCP list.

    Server tool list (6)

    Raw names from tools/list. Only developers need these.

    request_dataFREE, no payment. Describe in your own words the data you are trying to buy — anything, not just on-chain data — and get back whether we operate a service that supplies it, with the MCP endpoint if so. Every request is catalogued so repeatedly-requested data gets built. Nothing identifying is stored, only the words of the request.
    demand_reportFREE, no payment. The aggregate of what agents have told us they are looking for, most-requested first, with the categories nothing available yet serves.
    gas_nowLive gas price on Ethereum, Base, Arbitrum, Optimism or Polygon — in wei and gwei, plus what a plain 21,000-gas transfer would cost in the native token, which is the number you actually budget with. Pass several chains comma-separated to compare where to execute. Call this immediately before sending a transaction: gas moves every block, so the answer is good for seconds, not minutes. Costs $0.005 USDC per call via x402 on Base.
    token_infoRead an ERC-20's name, symbol, decimals and total supply straight from the contract on the chain you name, and confirm the address actually has code there. Use before quoting an amount or building a transfer: getting decimals wrong is the classic way to send 1,000,000x the intended value. An address with no code, or a contract that is not an ERC-20, is reported as such and is NOT charged. Costs $0.005 USDC per call via x402 on Base.
    tx_statusStatus of a transaction by hash: success, failed or still pending, with the block it landed in, sender and recipient, value moved, gas used, the fee actually paid, and how many logs it emitted. Use to confirm an action you took really settled rather than assuming it did. An unknown hash is reported as not_found and is NOT charged. Costs $0.005 USDC per call via x402 on Base.
    address_infoNative balance, the next nonce to use, and whether the address holds contract code — the three things needed before sending from or to an address. Pass 'token' as well to read an ERC-20 balance for the same address in the same call. Values are read at the latest block, so a reorg can change them. Costs $0.008 USDC per call via x402 on Base.