I put an MCP server behind HTTP 402. Here's the exact setup.
AI agents are hitting APIs thousands of times a day and paying nothing. I wanted to know if the "pay per call" story is real or slideware, so I built the smallest possible version: my own knowledge base, sold per query, settled on-chain. It works. Here's everything, including the transaction. What it is Five MCP tools wrapping things I actually know — ComfyUI API-prompt fixes, node wiring…
An AI researcher built a simple, pay-per-query knowledge base on the Base blockchain, using the Coinbase MCP package. Each paid tool costs $0.005 per call, paid in USDC on Base. The server was built using the @x402/mcp package, the standard MCP server with StreamableHTTP transport via Express. A facilitator on PayAI's public Base mainnet handles the payment flow, verifying signatures and submitting USDC transfers on-chain.
The end-to-end settlement was measured on the Sepolia testnet and confirmed on the Base mainnet. The server runs on a Google Cloud e2-micro free-tier VM and costs nearly nothing to operate. The researcher believes that real demand for micro-payments will come from businesses whose APIs are currently being scraped for free.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
