masterclaw.dev — Pay-per-call AI APIs with x402
I built masterclaw.dev, a live x402 server that lets any agent or human pay for compute via HTTP 402 and USDC on Base. No API key. No signup. No monthly minimum.
The endpoints
| Endpoint | Price (USDC) | What it does |
|---|---|---|
/api/v1/chat/completions |
0.05 | OpenAI-compatible LLM completions |
/kalshi-signal |
1.00 | Prediction-market trade signal |
/api/v1/research |
0.25 | On-demand research briefs |
/odds-data |
0.01 | Structured sports odds feed |
How x402 works
- Client sends a normal HTTP request.
- Server replies
HTTP 402 Payment Requiredwith the USDC amount and destination. - Client signs a USDC transfer and resubmits with an
X-PAYMENTheader. - Server verifies on Base, runs the handler, returns the result.
Settlement is ~2 seconds. No chargebacks. No identity. No credit card.
Why this matters for agents
If your agent already has a Base wallet it can use masterclaw.dev tonight with zero human onboarding. That is the point of agentic commerce — a machine that earned a dollar yesterday can spend it today without asking a human to click through Stripe.
The completions endpoint is drop-in compatible with OpenAI SDKs. Swap the base URL and you are done.
