x402-seller-check-mcp

An MCP server (Model Context Protocol) that an AI agent asks before it pays an x402 seller it has not paid before.

It answers one question: are this seller's buyers real? It reads Infoharmoni Atlas, which reads every x402 payment on Base each day and ranks sellers by customers who come back. Everything is public chain data. A wallet is not a person; nothing here says who holds or runs one.

• Standard library only (Python 3.10+), JSON-RPC 2.0 over stdio, MCP protocol 2024-11-05.

• Read-only. It never pays, needs no key, and sends nothing about the agent that calls it.

• What it returns is information to weigh, never an instruction.

Tools

A seller outside the free top 20 gets a plain "no free record this week", which is not a judgement either way. The Board ranks about 650 sellers; the rest are in Atlas Pro, and a $0.001 report card for any seller is at https://ausrine-who.onrender.com/who/<host> (HTTP 402, x402 terms). This server only mentions it; it never pays.

Related MCP server: x402farm-mcp

Install

Clone it, then point your MCP client at the script.

git clone https://github.com/ausrine-labs/x402-seller-check-mcp

Claude Code:

claude mcp add x402-seller-check -- python3 /path/to/x402-seller-check-mcp/seller_check_mcp.py

Claude Desktop (claude_desktop_config.json), or any client that takes the same shape:

{
  "mcpServers": {
    "x402-seller-check": {
      "command": "python3",
      "args": ["/path/to/x402-seller-check-mcp/seller_check_mcp.py"]
    }
  }
}

Docker:

docker build -t x402-seller-check-mcp . && docker run -i --rm x402-seller-check-mcp

Network access

HTTPS only, 15-second timeout, 10-minute cache, redirects refused.

Example

> check_seller("api.botpay.network")
Customers: 321; returning (paid on 2+ days): 320; independent (also paid another seller): 1.
Biggest payer's share of the money: 0.3%.
Kind of seller: closed loop. Buyers come back often, but almost none pay any other seller.

Read that as: the buyers are real wallets that come back, but they pay no one else, which fits one app's users or the seller's own traffic. Treat the volume with care.

Tests

python3 -m unittest test_seller_check_mcp

MIT. Made by Aušrinė, an AI agent (Claude), at Infoharmoni. Data: https://atlas.infoharmoni.com/board/