Short answer: no, x402 is not USDC-only. Any ERC-20 that implements EIP-3009 works — and USDG (Global Dollar) does. MadeOnSol already accepts USDG on Robinhood Chain for keyless, pay-per-call API access. If you've read that "x402 only supports USDC and EURC," that's out of date.
This post explains where the myth comes from, why USDG qualifies, and what that unlocks on Robinhood Chain.
Why people think x402 is "USDC only"
x402 is an open payment standard for machine-to-machine payments over HTTP — an AI agent calls an endpoint, gets an HTTP 402 Payment Required challenge, signs a payment, and receives the data. It launched with USDC on Base and Solana, and most early tutorials, SDK examples, and facilitator defaults use USDC. So the ecosystem shorthand became "x402 = USDC."
But that's a convention, not a constraint. The protocol's "exact" payment scheme on EVM chains is built on EIP-3009, not on USDC specifically.
What actually matters: EIP-3009
On EVM chains, x402's exact scheme settles a payment by calling transferWithAuthorization — the function defined by EIP-3009 ("Transfer With Authorization"). Instead of the payer sending a transaction and paying gas, the payer signs an EIP-712 typed-data message authorizing a single, exact-amount transfer to a specific recipient. A facilitator then submits that authorization on-chain and pays the gas. It's a gasless, signature-based transfer.
The requirement is therefore simple: any ERC-20 token that implements EIP-3009 can be used with x402's exact scheme. USDC implements it. EURC implements it. And so does USDG.
USDG implements EIP-3009
USDG (Global Dollar), issued by Paxos, is an EIP-3009-compatible stablecoin — its contract exposes transferWithAuthorization, the same gasless-transfer primitive USDC uses. It also supports EIP-2612 permits. In other words, USDG carries exactly the on-chain machinery x402's exact scheme needs.
We verified this on Robinhood Chain directly. USDG on Robinhood Chain (contract 0x5fc5…d168, 6 decimals — the dominant stablecoin on the chain) exposes a live EIP-712 domain and behaves identically to mainnet USDG on the authorization functions. Its EIP-712 domain is { name: "Global Dollar", version: "1", chainId: 4663 }, and the settlement call is the standard transferWithAuthorization(from, to, value, validAfter, validBefore, nonce, v, r, s). That's all x402 needs.
What this unlocks on Robinhood Chain
Because USDG supports EIP-3009, an AI agent operating on Robinhood Chain can pay for data in the stablecoin it already holds, on the chain it already operates on — no bridging to Solana, no acquiring USDC, no separate wallet. It signs one authorization; the facilitator settles it on Robinhood Chain in about a second.
MadeOnSol uses exactly this. Every Robinhood Chain intelligence endpoint is available keyless and pay-per-call, settling in USDG on Robinhood Chain via EIP-3009 — the first KOL and deployer intelligence API on Robinhood Chain payable per call in USDG. And because x402 lets one endpoint advertise more than one payment option, each endpoint is dual-accept: pay in USDG on Robinhood Chain, or USDC on Solana, whichever your agent holds. (More on that design in Dual-Accept x402.)
The myth vs the reality
| Claim | Reality |
|---|
| "x402 only works with USDC" | x402's exact scheme works with any EIP-3009 token |
| "USDG can't be used for x402" | USDG implements EIP-3009 — it works today |
| "You need Base or Solana for x402" | x402 works on any EVM chain you configure, including Robinhood Chain (chain id 4663) |
| "The payer needs the chain's gas token" | No — the payer signs off-chain; the facilitator pays gas |
Try it
You don't need an account or an API key to test it — the wallet is the key. Hit the free discovery endpoint to see the live catalog and payment options:
curl https://madeonsol.com/api/x402/rhc
Then read How AI Agents Pay for Robinhood Chain Data in USDG for the full payment flow, or see the endpoints and pricing on the Robinhood Chain x402 page.
Prefer a flat monthly plan (Robinhood Chain is bundled into every tier at no extra cost)? See madeonsol.com/pricing.
FAQ
Does x402 only work with USDC?
No. x402's exact payment scheme on EVM chains works with any ERC-20 token that implements EIP-3009. USDC and EURC implement it — and so does USDG (Global Dollar). x402 is not USDC-only; the constraint is EIP-3009 support, not the specific token.
Does USDG support EIP-3009?
Yes. USDG (Paxos Global Dollar) implements EIP-3009's transferWithAuthorization, the gasless signed-transfer primitive that x402's exact scheme uses. It also supports EIP-2612 permits. That is exactly the on-chain machinery x402 needs.
Can you use x402 on Robinhood Chain?
Yes. x402 works on any EVM chain you configure, including Robinhood Chain (chain id 4663). MadeOnSol settles x402 payments natively in USDG on Robinhood Chain today, across ten KOL, token, wallet and deployer intelligence endpoints.
Does the payer need the chain's gas token to pay with x402?
No. With the EIP-3009 exact scheme the payer only signs a payment authorization off-chain — it never submits a transaction. A facilitator broadcasts the authorization and pays the gas, so the payer needs only the stablecoin (e.g. USDG), not the chain's gas token.
MadeOnSol is a data provider — KOL, deployer, and token intelligence across Solana and Robinhood Chain. We don't execute trades or hold custody; the x402 payment moves wallet-to-wallet directly.
