supra-x402

Official x402 v2 payment support for the Supra Network.

Pay any HTTP API with signed, on-chain-settled payments on Supra — gasless or self-paid, from agents, servers, or wallets. Built on @x402/core v2, so it interoperates with the standard x402 ecosystem.

npm i supra-x402 @x402/core @x402/fetch

• exact scheme for Supra's Move VM — Ed25519 signatures, BCS transfer authorizations, verified/settled against Supra RPC (no EIP-3009; that's EVM-only).
• Coin and Fungible Asset assets; sponsored (gasless) and self-paid gas.
• Off-chain relay — no Move contract to deploy or audit. Replay-protected by sequence number, expiry by transaction timeout.
• DX: server helper for Next.js/Express/Hono middleware, a React hook, and raw-key + wallet signers.

Networks

| CAIP-2 | Network | Chain id | | --------- | ------- | -------- | | supra:6 | testnet | 6 | | supra:8 | mainnet | 8 |

Accept payments (server)

createSupraResourceServer returns a server that plugs into the official framework middleware:

// Next.js middleware.ts
import { paymentMiddleware } from "@x402/next";
import { createSupraResourceServer } from "supra-x402/server";

export const middleware = paymentMiddleware(
  { "/api/report": { price: "0.10", network: "supra:6" } },
  createSupraResourceServer({ facilitatorUrl: "https://supra-x402-facilitator.vercel.app" }),
);
export const config = { matcher: ["/api/report"] };

@x402/express and @x402/hono work the same way — pass the same server to their paymentMiddleware.

Pay (client / agent)

import { x402Client } from "@x402/core/client";
import { wrapFetchWithPayment } from "@x402/fetch";
import { registerSupraExact, keySignerFromPrivateKey } from "supra-x402/client";

const client = registerSupraExact(new x402Client(), {
  network: "supra:6",
  signer: keySignerFromPrivateKey(process.env.SUPRA_PRIVATE_KEY!),
});

const res = await wrapFetchWithPayment(fetch, client)("https://api.example.com/api/report");

React

"use client";
import { usePayWithX402 } from "supra-x402/react";

const { payJson } = usePayWithX402({ signer, network: "supra:6" });
const data = await payJson("/api/report");

Run a facilitator

import { x402Facilitator } from "@x402/core/facilitator";
import { createSupraClient, SupraExactFacilitator, SupraFacilitatorSigner } from "supra-x402";
import { SupraAccount, HexString } from "supra-ts-sdk";

const signer = new SupraFacilitatorSigner({
  accounts: [new SupraAccount(HexString.ensure(process.env.FEE_PAYER_KEY!).toUint8Array())],
  clients: { "supra:6": createSupraClient("supra:6") },
});
const facilitator = new x402Facilitator().register(["supra:6"], new SupraExactFacilitator(signer));
// expose facilitator.verify / .settle / .getSupported over /verify /settle /supported

Exports

| Import | Contents | | ------ | -------- | | supra-x402 | scheme classes, signer, createSupraClient, address/transfer/codec helpers, constants | | supra-x402/client | registerSupraExact, SupraExactClient, key signer | | supra-x402/server | createSupraResourceServer, createSupraFacilitatorClient, SupraExactServer | | supra-x402/react | usePayWithX402 | | supra-x402/wallets | keySignerFromPrivateKey, browserWalletSigner |

Security

The facilitator verifies the payer's Ed25519 signature over the exact Supra signing message and decodes the transfer entry function to confirm recipient, amount, and asset before broadcasting — it can never broadcast anything but the exact transfer the requirement demands. See the threat model.

License

MIT © Entropy Foundation