Install MCP Server (Claude Desktop & Code)

Install the Xenarch MCP server in Claude Desktop, Claude Code, Cursor, or any Model Context Protocol client. A single npx command wires up three tools for x402 payments — xenarch_check_gate, xenarch_pay, and xenarch_get_history — no cloning, no build step, no API key.

Prerequisites

Node.js 18+
A wallet with USDC on Base (+ small ETH for gas)

Claude Code

claude mcp add xenarch -- npx @xenarch/agent-mcp

Claude Desktop

Edit your config file:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "xenarch": {
      "command": "npx",
      "args": ["@xenarch/agent-mcp"],
      "env": {
        "XENARCH_PRIVATE_KEY": "0xYOUR_PRIVATE_KEY"
      }
    }
  }
}

Restart Claude Desktop after saving.

Other MCP clients

Any client that supports the MCP stdio transport can use the server:

npx @xenarch/agent-mcp

The server communicates over stdin/stdout using the MCP protocol.

Wallet configuration

Environment variable
Config file
Auto-generate

Set XENARCH_PRIVATE_KEY in the MCP server’s env block:

{
  "env": {
    "XENARCH_PRIVATE_KEY": "0xYOUR_PRIVATE_KEY"
  }
}

Create ~/.xenarch/wallet.json:

mkdir -p ~/.xenarch
cat > ~/.xenarch/wallet.json << 'EOF'
{
  "privateKey": "0xYOUR_PRIVATE_KEY"
}
EOF
chmod 600 ~/.xenarch/wallet.json

If no wallet is configured, the server generates one on first run and saves it to ~/.xenarch/wallet.json. Fund it with USDC before making payments.

Configuration variables

Variable	Default	Description
`XENARCH_PRIVATE_KEY`	—	Wallet private key
`XENARCH_NETWORK`	`base`	`base` or `base-sepolia`
`XENARCH_RPC_URL`	`https://mainnet.base.org`	Base RPC endpoint
`XENARCH_API_BASE`	`https://api.xenarch.dev`	Platform API
`XENARCH_AUTO_APPROVE_MAX`	—	Auto-approve payments up to this USD amount

Testnet

For testing without real funds:

{
  "mcpServers": {
    "xenarch": {
      "command": "npx",
      "args": ["@xenarch/agent-mcp"],
      "env": {
        "XENARCH_PRIVATE_KEY": "0xYOUR_PRIVATE_KEY",
        "XENARCH_NETWORK": "base-sepolia",
        "XENARCH_RPC_URL": "https://sepolia.base.org"
      }
    }
  }
}

Troubleshooting

Tools not appearing: Restart your MCP client. Verify npx @xenarch/agent-mcp runs without errors in your terminal. “No wallet configured”: Set XENARCH_PRIVATE_KEY or create ~/.xenarch/wallet.json. “Insufficient USDC”: Fund your wallet with USDC on Base. You also need a small amount of ETH for gas (~$0.01).

Getting Started

MCP Server

Smart Contract

Integrations

Examples

Install MCP Server (Claude Desktop & Code)

Prerequisites

Claude Code

Claude Desktop

Other MCP clients

Wallet configuration

Configuration variables

Testnet

Troubleshooting

​Prerequisites

​Claude Code

​Claude Desktop

​Other MCP clients

​Wallet configuration

​Configuration variables

​Testnet

​Troubleshooting

Prerequisites

Claude Code

Claude Desktop

Other MCP clients

Wallet configuration

Configuration variables

Testnet

Troubleshooting