x402-mcp

MCP server bringing hundreds of x402-paid APIs to AI agents (Claude, Cursor, MCP-aware clients). Auto-discovers tools from CDP Bazaar; handles USDC micropayments on Base + Solana.

Features

Auto-discovers x402 endpoints from CDP Bazaar (no hard-coded list)
Reads metadata directly from Bazaar (description, schema, pricing)
Refreshes every 5 min — new endpoints appear without restart
Handles HTTP 402 + USDC payment automatically
Multi-chain: Base + Solana mainnet live (USDC on both); Polygon/BNB/EVM expandable

Install (Claude Desktop)

Add to claude_desktop_config.json:

config.json

{
  "mcpServers": {
    "x402-mcp": {
      "command": "npx",
      "args": ["-y", "x402node-mcp"],
      "env": { "X402_PRIVATE_KEY": "0xYOUR_BASE_PRIVATE_KEY" }
    }
  }
}

Set X402_PRIVATE_KEY to a Base EOA private key (hex, 0x-prefixed) with USDC on Base mainnet (Solana payment via SPL USDC also supported). Restart Claude Desktop. The server auto-discovers ~117 tools on first run.

Cost Safety

Each tool call costs $0.0001-$0.10 USDC depending on endpoint
Hard cap: MAX_PRICE_USD env var (default $0.10/call); calls above are blocked
Use a fresh burner wallet, not your main wallet

How it works

Agent calls tool -> HTTP 402 -> x402-fetch signs EIP-3009 -> CDP Facilitator settles on Base or Solana -> response returned. Buyer pays no gas.

Development

bash

git clone https://github.com/x402node/x402-mcp
cd x402-mcp
npm install
cp .env.example .env  # edit X402_PRIVATE_KEY
node mcp-server.js

License

MIT

X402 MCP README