First Call Free

Try a paid x402 API on Base mainnet for net $0. Not a demo key, not a sandbox — a real HTTP 402 payment and a real on-chain refund.

✅ Rebate rail live ✅ First rebate settled on-chain (Nov 9, 2026) ✅ Base mainnet USDC

How it works — charge and rebate

The service charges its normal $0.05 USDC x402 challenge. After your payment settles on Base, the RAEN rebater sends the $0.05 straight back to your wallet. Net cost: $0.00.

Why not just a free endpoint? Because the point is to prove the real payment path — you experience the actual x402 402-challenge → EIP-3009 settlement → USDC rebate loop, end to end. Free tier fakes it; this doesn't.

Steps

Have a wallet with a little ETH for gas on Base (the settlement is an on-chain EIP-3009 transfer — even though the payment is rebated, the gas is yours).

POST to the law-lookup endpoint with your address in the x-payer-address header. You'll get an HTTP 402 with a payment challenge.

Pay the challenge with any x402 client (or the RAEN cookbook recipes).

Within seconds of settlement, the rebater pays $0.05 USDC back to your address. Check it on Basescan.

One free call per wallet per 30 days. The rebate is keyed to settled payments — an unpaid challenge gets no rebate. The rebate treasury (AgentCash) is capped at 100 rebates/day; if it's exhausted, the call simply isn't rebated that day.

Copy-paste

curl -s -X POST https://royal-ruby-x402.fly.dev/api/law-lookup \
  -H 'Content-Type: application/json' \
  -H 'x-payer-address: 0xYOUR_WALLET' \
  -d '{"question":"How long does a credit bureau have to investigate a dispute?"}'

The 402 response's payment-required header carries a base64 challenge — decode it and you'll see payTo: 0x9b8a27e0…, network: eip155:8453, scheme: exact. Pay it with the x402 client from the cookbook and your answer JSON comes back.

Live, right now

Loading live fleet numbers…

Rendered in your browser straight from the settlement collector's own public ledger — the same machine that records every settlement. No marketing overlay.

Verify everything

We don't ask you to trust the rebate — verify it:

Proof of Commerce ledger — live fleet telemetry, no marketing overlay
The Transparent Company — our operating law, published as a promise. If you're one of the few who found this page, read To the nine on it.
Rebater health — live rebate count and treasury
Service manifest — pricing and terms, machine-readable
The rebate itself lands as a USDC Transfer on Base — look up your address on Basescan after paying
x402 Payback Calculator — see what pay-per-call costs vs a flat subscription at your volume

What you get

royal-ruby-x402 — US consumer-rights law citation lookup: structured FCRA, FDCPA, TILA, state UDAP, reporting timelines, and statutes of limitations. Information only, not legal advice. A taste of the 12-service RAEN fleet: full directory, MCP gateway (listed on the MCP Registry).