dev.true402/mcp-server

@true402.dev/mcp-server

MCP server for the true402 machine-native marketplace — give your agent pay-per-call access to AI inference and web tools over x402 (HTTP 402 micropayments in USDC on Base).

No accounts, no API keys. The agent's wallet is its identity: each paid tool returns an HTTP 402 challenge, the server signs an EIP-3009 USDC authorization, and the call settles on-chain. Configure a funded wallet to auto-pay, or run without one and the paid tools will surface the exact payment requirements instead of failing.

Tools

Tools are auto-discovered from the live catalog at startup, so a new marketplace stall appears without an update to this package. The catalog currently yields:

Prices are indicative; the live 402 challenge is authoritative, and the server refuses to sign above its per-call cap. Call list_models or read https://true402.dev/api/openapi.json for the exact set.

Install

Requires Node.js ≥ 20. Runs over stdio — point any MCP client at it via npx.

Claude Desktop / Claude Code

Add to your MCP config (claude_desktop_config.json, or .mcp.json for Claude Code):

{
  "mcpServers": {
    "true402": {
      "command": "npx",
      "args": ["-y", "@true402.dev/mcp-server"],
      "env": {
        "WALLET_PRIVATE_KEY": "0xYOUR_FUNDED_BASE_WALLET_KEY"
      }
    }
  }
}

Cursor / Cline / other MCP clients

Same idea — command npx, args ["-y", "@true402.dev/mcp-server"], and the WALLET_PRIVATE_KEY env var.

Configuration

Security: the key is read only from the environment and is never logged, echoed, or returned. Use a dedicated low-balance wallet — fund it with only what you intend to spend.

How payment works

1. The tool calls the true402 endpoint with no payment.
2. The server replies 402 with accepted payment options (USDC on Base).
3. This MCP server signs an EIP-3009 transferWithAuthorization with your wallet.
4. It retries with the signed payment in the PAYMENT-SIGNATURE header (x402 v2); the service verifies and responds.
5. Settlement happens on-chain. Your wallet pays only USDC — the facilitator sponsors gas.

When a newer release of this server exists, the first tool result of the session carries one extra line saying so, with the install command. Nothing is blocked; it is shown once per process.

Links

• Marketplace: https://true402.dev
• Free Telegram rug-check bot (no wallet): https://t.me/True402bot
• Live tool catalog: https://true402.dev/api/v1/services
• x402 protocol: https://x402.org

Guides

• The x402 protocol, explained
• x402 facilitators: what they do and which to use
• Fund a Base wallet for x402 (USDC only, no ETH)

Also available for

MCP (Claude Code / Desktop, Cursor, Hermes) · Hermes Agent · OpenClaw · ElizaOS · LangChain · CrewAI · Vercel AI SDK · Coinbase AgentKit · Virtuals GAME · CLI — same on-chain checks, one install command each: true402.dev/integrations

Paying, exactly

The rules below are the service's, not this package's — they bite whatever client you use, and they are the ones that surprise people writing their own payer.

• Pay the EXACT amount quoted in the 402. Underpaying is rejected. Overpaying is refused with 402 and never credited — settlement submits the signed value and there is no refund path, so a surplus would simply be swept. Equality is also what binds an authorization to the resource it was quoted for.
• One authorization buys exactly one response. A replay is refused, not double-charged.
• You are charged on success only. Settlement is submitted only when the endpoint returns 2xx; if it errors or times out, your signed authorization is never submitted, so there is nothing to refund.
• Some endpoints serve a few free calls per day per client IP, with no wallet. The per-operation description in the OpenAPI spec says which.

Full rules: true402.dev/terms · what is logged and kept: true402.dev/privacy

License

MIT