HTTP/1.1 402 PAYMENT REQUIRED agent402.base.eth · BASE · SOLANA · POLYGON · ARBITRUM · ROBINHOOD · USDC · USDG
Agent402 / tools / onramp-link

Onramp link (fund a wallet with a card)

$0.001 per call · USDC via x402 · POST /api/onramp-link

Generate a single-use Coinbase Onramp URL that lets a human fund any wallet with a card or Apple Pay — the fastest way to put real USDC into an agent's wallet. Returns the ready-to-open URL plus a fee-inclusive quote. Networks: base, ethereum, polygon, arbitrum, optimism, solana.

Input

FieldTypeDescription
address *stringDestination wallet address (EVM 0x… or Solana base58, matching the network)
networkstringbase (default) | ethereum | polygon | arbitrum | optimism | solana
assetstringTicker to purchase (default USDC)
amountstringCrypto amount the wallet should receive (default 10)
countrystringBuyer's ISO 3166-1 country code (default US)
subdivisionstringUS state code (e.g. NY) — required for US buyers by some payment methods
redirectUrlstringOptional URL to send the buyer to after checkout

Example output

{
  "onrampUrl": "https://pay.coinbase.com/…single-use…",
  "singleUse": true,
  "quote": {
    "paymentTotal": "10.42",
    "paymentCurrency": "USD",
    "purchaseAmount": "10",
    "purchaseCurrency": "USDC",
    "destinationNetwork": "base"
  }
}

Try it — see the 402 challenge (free)

curl -i -X POST https://agent402.tools/api/onramp-link \
  -H "Content-Type: application/json" \
  -d '{"address":"0xaBF4FAbd7c416fB67202E5f9002389Fc75e2a9D0","network":"base","amount":"10"}'

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/onramp-link", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "address": "0xaBF4FAbd7c416fB67202E5f9002389Fc75e2a9D0",
    "network": "base",
    "amount": "10"
  }),
});
Wallet-only. This tool reaches the network/browser/storage, so it is paid in USDC via x402 (no proof-of-work tier).

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