402md MCP Server

@402md/mcp

MCP server that transforms SKILL.md files into executable tools for AI agents. Point to any skill — URL, local file, or marketplace name — and the server parses it, auto-pays via x402, and returns the result.

Quick Start

npx @402md/mcp

Or install globally:

npm install -g @402md/mcp
402md-mcp

The server starts in read-only mode by default. You can browse and inspect skills immediately. To execute paid endpoints, configure a wallet (see Wallet Setup).

Networks

The server supports four networks across two blockchain ecosystems:

Stellar

Stellar is the default and preferred network. It offers sub-second finality, near-zero fees (~0.00001 XLM per tx), and native USDC support.

• Testnet faucet: Use Stellar Laboratory to create and fund testnet accounts.
• Mainnet: Fund your account via any Stellar DEX, exchange, or on-ramp that supports USDC on Stellar.

EVM (Base)

Base is an Ethereum L2 with low gas fees and fast confirmations.

• Sepolia faucet: Get testnet ETH from Alchemy Faucet or Coinbase Faucet (needed for gas). Then bridge or mint testnet USDC.
• Mainnet: Bridge USDC to Base from Ethereum, or buy directly on Base via Coinbase or any supported on-ramp.

Choosing a Network

• Just getting started? Use stellar-testnet — no real money, instant setup with create_wallet.
• Testing EVM skills? Use base-sepolia — free testnet, good for EVM-specific endpoints.
• Production? Use stellar (lower fees) or base depending on what the skill accepts.

The server automatically selects the best compatible network when calling a skill. If a skill supports multiple networks and your wallet has both keys configured, Stellar is preferred.

Wallet Setup

There are three ways to configure a wallet, listed by priority (highest first):

Option 1: Environment Variables (recommended for production)

# Stellar
export STELLAR_SECRET="SCZANGBA5YHTNYVVV3C7CAZMCLXPILHSE6PGYV2FHHUQ5DGQJWRZ4GXT"
export NETWORK="stellar-testnet"

# EVM (Base)
export EVM_PRIVATE_KEY="0x4c0883a69102937d6231471b5dbb6204fe512961708279f23efb3c0c90..."
export NETWORK="base-sepolia"

# Both (FULL mode)
export STELLAR_SECRET="S..."
export EVM_PRIVATE_KEY="0x..."
export NETWORK="stellar"  # default network when both are available

Option 2: `create_wallet` Tool (recommended for development)

If no wallet is configured, ask your AI agent to use the create_wallet tool:

"Create a new wallet on stellar-testnet"

This generates a keypair and saves it to ~/.402md/wallet.json. The server reloads automatically.

Important: create_wallet refuses to run if a wallet is already configured. To replace an existing wallet, delete ~/.402md/wallet.json manually first.

Option 3: Wallet File (manual)

Create ~/.402md/wallet.json manually:

{
  "stellarSecret": "SCZANGBA5YHTNYVVV3C7CAZMCLXPILHSE6PGYV2FHHUQ5DGQJWRZ4GXT",
  "evmPrivateKey": "0x4c0883a69102937d6231471b5dbb6204fe512961708279f23efb3c0c90...",
  "network": "stellar-testnet",
  "createdAt": "2026-01-15T10:30:00.000Z"
}

The file is created with 0o600 permissions (owner read