Developer tools

x402Fi demo: paid hello

A cent buys a signed hello. The fastest way to see x402 work end to end.

Built-in demo run by x402Fi. Pay $0.01 in USDG on Robinhood Chain and get a JSON response that names the paying wallet. Use it to test an agent, a wallet, or your finance export.

Endpoint

x402Fi demo: paid hello

A cent buys a signed hello. The fastest way to see x402 work end to end.

GET/g/demo-quote/…

$0.01

per call

GET https://x402fi.dev/g/demo-quote?symbol=USDG

# 402 Payment Required → sign USDG → retry with PAYMENT-SIGNATURE

Example response

{
  "symbol": "USDG",
  "message": "Paid response delivered by x402Fi.",
  "paidBy": "0x…",
  "servedAt": "2026-11-08T12:00:00.000Z"
}

Needs USDG on Robinhood Chain. No gas: x402Fi pays it.