The latest articles on DEV Community by kevin2003050666-coder (@kevin2003050666coder). https://dev.to/kevin2003050666coder https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F4104142%2Fed2ebdec-252a-4c1b-a38f-17b1b305e7bb.png https://dev.to/kevin2003050666coder en kevin2003050666-coder Tue, 01 Sep 2026 10:29:38 +0000 https://dev.to/kevin2003050666coder/what-a-seller-side-http-402-mcp-paywall-looks-like-36n https://dev.to/kevin2003050666coder/what-a-seller-side-http-402-mcp-paywall-looks-like-36n <p>I needed agents to pay per call against an existing HTTP API without handing out API keys. x402-micro-tollgate is a thin Express process that is both an HTTP 402 reverse proxy and an MCP server.</p> <p>Unpaid gated routes (default <code>/v1</code>) return protocol 402. After settlement, the request is proxied to UPSTREAM_URL. <code>/health</code> stays free. Same process exposes MCP tools: <code>server_info</code> (free), <code>get_quote</code> / <code>proxy_request</code> (paid).</p> <p>Demo (no CDP keys):</p> <div class="highlight js-code-highlight"> <pre class="highlight plaintext"><code>curl -i https://x402-micro-tollgate.onrender.com/v1/quote # HTTP/1.1 402 Payment Required </code></pre> </div> <p>Self-host:</p> <div class="highlight js-code-highlight"> <pre class="highlight plaintext"><code>npx x402-micro-tollgate </code></pre> </div> <p>Repo: <a href="https://github.com/kevin2003050666-coder/x402-micro-tollgate" rel="noopener noreferrer">https://github.com/kevin2003050666-coder/x402-micro-tollgate</a><br> npm: <a href="https://www.npmjs.com/package/x402-micro-tollgate" rel="noopener noreferrer">https://www.npmjs.com/package/x402-micro-tollgate</a><br> MCP Registry: <code>io.github.kevin2003050666-coder/x402-micro-tollgate</code></p> x402 mcp javascript