I Built an x402 Server That Lets AI Agents Pay Me While I Sleep

I spent 45 days building MASTERCLAW — a fully autonomous income system running on a DigitalOcean VPS in New York. Kalshi trading bots, research scouts, prediction market scanners, all running 24/7 while I sleep in Sacramento.
Then I discovered x402. And everything changed.
What is x402?
x402 is a payment protocol built by Coinbase. When an AI agent hits your server and needs to pay, your server returns HTTP 402 — Payment Required. The agent automatically pays USDC on Base. Your wallet receives the funds. No human involved. No checkout. No Stripe. No credit card.
The entire transaction takes 2 seconds.
What I built
masterclaw.dev is a live x402 server with 4 paid endpoints:
EndpointPriceWhat it does/api/v1/chat/completions$0.05 USDCOpenAI-compatible AI completions via DeepSeek/kalshi-signal$1.00 USDCLive prediction market signals/api/v1/research$0.25 USDCNightly research intel from Reddit, HN, web/odds-data$0.01 USDCLive sports odds feed
The economics
DeepSeek costs me $0.0000076 per call. I charge $0.05. That's 99.9% margin on every transaction. An agent can call my endpoint 2.6 million times before I spend $20 in costs.
I watched a seller on x402scan do $3,290 in one day from 3 buyers. Another did $432,000 total from just 2 endpoints priced at $0.001 each.
How any agent can use it
If your agent has a Base wallet it can use masterclaw.dev tonight. No signup. No API key. No monthly fee. Just call the endpoint, pay the 402, get the data.
The completions endpoint is drop-in compatible with any OpenAI SDK. Swap the base URL and you are done.
Try it
agentcash try https://masterclaw.dev
Or call directly:
POST https://masterclaw.dev/api/v1/chat/completions
This is what agentic commerce looks like. Machines paying machines. No humans required.