X402 Payment Gated Http

What is X402 Payment Gated Http?

X402 Payment Gated Http is an MCP server that lets AI agents call HTTP APIs using the x402 protocol. When an API responds with a 402 Payment Required status, the server automatically handles the payment challenge, builds the proof, retries the request, and returns the final response.

How to use X402 Payment Gated Http?

Install via npx @merkleworks/x402-mcp. Configure in your MCP client (e.g., Cursor’s .cursor/mcp.json) by pointing the command to that package. Then invoke tools such as paid_http_request with a URL and method to make payment-gated HTTP calls.

Key features of X402 Payment Gated Http

• paid_http_request – sends an HTTP request and automatically handles 402 challenges.
• discover_x402_api – finds payable endpoints (e.g., from /.well-known/x402 or probing).
• pay_x402_endpoint – calls a known x402 endpoint with full control.
• parse_x402_challenge / verify_x402_proof – inspect and verify x402 headers.
• Runs entirely via npx; no separate installation steps required.

Use cases of X402 Payment Gated Http

• AI agents accessing premium APIs that require micropayments per request.
• Automating calls to a paywalled data source without manual payment handling.
• Discovering and interacting with unknown x402-enabled endpoints programmatically.
• Testing and debugging x402 protocol headers from within an MCP environment.

FAQ from X402 Payment Gated Http

What is the x402 protocol?

x402 is a protocol that allows HTTP APIs to request payment (402 status) and include a challenge; the client then constructs and attaches a cryptographic proof of payment to retry the request.

How does the automatic payment flow work?

When an API responds with 402, the server parses the challenge, builds the required payment, retries the request with the proof, and returns the API’s final response.

What tools does the MCP server provide?

It offers paid_http_request (main), discover_x402_api, pay_x402_endpoint, parse_x402_challenge, and verify_x402_proof.

What are the runtime dependencies?

The server runs via npx and only requires Node.js. No additional libraries or wallets are mentioned in the README.

How is the server invoked in an MCP client?

Add it to the MCP configuration (e.g., mcpServers.x402 in .cursor/mcp.json) with command: "npx" and args: ["@merkleworks/x402-mcp"].