X402 Gateway MCP Server

Retired source — recovery reference

Active maintenance moved to the sole maintained private repository Marysbrain/aye-today, in packages/mcp/.

Do not install or deploy from this retired repository. The historical instructions below are retained for recovery and reference, not current operations.

Existing public deployments continue unchanged. Repository retirement does not delete or shut down services. Original source and Git history remain preserved; retired repository workflows are disabled.

Retirement notice: 2026-09-03.

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x402-gateway-mcp

The live x402 market feed for agents. The x402_market_pulse tool is FREE — no wallet, no payment, no signup: the x402 ecosystem in one snapshot, refreshed ~3x/day — service listings by category with week-over-week deltas, newly listed services, npm download trends for the core x402 packages, protocol release tags, and per-source reliability grades. Every metric carries a freshness stamp; a stale source says so instead of pretending.

Behind the feed, Aye Scout exposes two paid pre-payment diligence tools: x402 category coverage and a resource preflight that checks reachability, terms, catalog presence, and observed age before an agent spends. The tool list is fetched from the signed public manifest at startup; compatibility-only routes are deliberately absent (verify).

The manifest is verified over its exact response bytes before any paid tools are registered. Both the treasury address and gateway signing-key ID are pinned; an unsigned manifest or an unexpected key rotation stops startup.

⚠️ Funded-wallet warning: WALLET_PRIVATE_KEY signs real payments. Use a dedicated wallet holding only small balances (a few dollars of USDC). Never your main wallet. The key is read from env, never logged, and payment headers are never echoed into agent-visible output.

5-minute setup (Claude Desktop / Claude Code)

1. Create a fresh wallet and fund it with a small amount of USDC on Base (or Base Sepolia test USDC from https://faucet.circle.com while testing).
2. npm install -g x402-gateway-mcp (or use npx).
3. Add to your MCP config (Claude Desktop claude_desktop_config.json, or claude mcp add for Claude Code):

{
  "mcpServers": {
    "x402-gateway": {
      "command": "npx",
      "args": ["-y", "x402-gateway-mcp"],
      "env": {
        "GATEWAY_URL": "https://<your-gateway-host>",
        "WALLET_PRIVATE_KEY": "0x<small-balance-wallet-key>",
        "MAX_PER_CALL_USD": "0.25",
        "MAX_SESSION_USD": "2.00"
      }
    }
  }
}

1. Restart the client. The free x402_market_pulse tool works immediately (no wallet needed); every paid tool description states its price, e.g. [costs $0.01 USDC per call] Score an x402 resource before paying it…

Spend guardrails

• MAX_PER_CALL_USD (default 0.25): tools priced above this are refused.
• MAX_SESSION_USD (default 2.00): cumulative settled spend per server session; calls that would exceed it are refused with a clear message the agent can relay. Restart the server to reset.

Refusals happen before any payment is signed.

Env reference

If a transport or body-read error occurs after payment authorization, the MCP reserves the full advertised amount as possibly spent. It will not silently restore that session capacity; reconcile the wallet before retrying.