gap133 on Arc

Pay one cent in USDC on Arc and get gap133's live, verified cross-venue prediction-market gaps. No account, no subscription, no API key. Every answer is signed, so an agent can prove it came from gap133.

00 / Free sample

Loading the biggest gap…

01 / Ask live

The sample above is one gap from a snapshot up to 10 minutes old. Paying 0.01 USDC returns the live board, with gaps after fees, signed by the attester.

Needs MetaMask (or any EVM wallet) on Arc mainnet with a few cents of USDC.

02 / Answer

Nothing yet.

03 / On-chain usage

–paid queries
–unique wallets
–USDC collected

Counted from the contract's Paid events on Arc mainnet, not from our own database. Anyone can recount them on the explorer.

04 / Use it inside Claude

Ask Claude "what are the biggest market gaps right now?" and it answers from gap133. For live answers it pays the 1¢ itself and checks the signature first.

Download for Claude DesktopMac and Windows · 113 KB · no Terminal needed
  1. Double-click the downloaded gap133.mcpb file. Claude Desktop opens and asks to install it. Click Install.
  2. That's it for the free tools. For live answers, paste the private key of a new wallet made just for this, holding a few cents of USDC on Arc (each answer is 1¢). Claude keeps it in your system keychain, and the extension stops at your spending limit (10¢ by default).
  3. In a new chat, ask: "Use gap133 to get the live top gaps."

Before every payment it checks that it is paying the official gap133 contract at the on-chain price. Never use your main wallet.

Claude Code, Cursor and other MCP apps 
claude mcp add gap133 -- npx -y https://codeload.github.com/Romil10/gap133-arc/tar.gz/main

# any MCP client config:
{
  "mcpServers": {
    "gap133": {
      "command": "npx",
      "args": ["-y", "https://codeload.github.com/Romil10/gap133-arc/tar.gz/main"],
      "env": { "GAP133_AGENT_KEY": "0x… dedicated wallet, a few cents of USDC on Arc",
               "GAP133_MAX_SPEND_USDC": "0.10" }
    }
  }
}

Without a key, the free tools still work. Details in the README.

How it works

contractloading…

The service answers your first request with HTTP 402 Payment Required and a one-time nonce. You call pay(nonce) on the contract with the exact price in native USDC. The service reads the payment on Arc (finality is under a second) and returns the data with the attester's signature in the X-Signature header. The attester address is stored in the contract, so anyone can check it.

curl -i https://arc.gap133.xyz/api/query?kind=top
# -> 402 { nonce, challenge, contract, price }
# pay(nonce) on Arc, then:
curl https://arc.gap133.xyz/api/query?kind=top \
  -H "X-Payment-Challenge: <challenge>" -H "X-Payment-Tx: <tx hash>"

Scripts: see examples/agent.mjs for a plain Node agent that pays and verifies on its own.