Primer x402 TypeScript SDK v1.1.0

Primer ecosystem toolkit for TypeScript. Use with the official x402 SDK packages.

npm @primersystems/x402

Installation

npm install @primersystems/x402

Peer Dependencies

The SDK requires @x402/core as a peer dependency:

# For Express middleware
npm install @x402/core @x402/express

# For Hono middleware
npm install @x402/core @x402/hono

# For Prism (ERC-20 payments)
npm install viem

Facilitator Client

Create a pre-configured client for the Primer facilitator:

import { primerFacilitator, PRIMER_FACILITATOR_URL } from '@primersystems/x402';

// Create facilitator client
const facilitator = primerFacilitator();

// Use with official x402 middleware
import { paymentMiddleware } from '@x402/express';

const routes = {
  '/api/premium': {
    price: '$0.01',
    network: 'eip155:8453',
    payTo: '0xYourWalletAddress'
  }
};

app.use(paymentMiddleware(routes, { facilitator }));

With Hono

import { Hono } from 'hono';
import { paymentMiddleware } from '@x402/hono';
import { primerFacilitator } from '@primersystems/x402';

const app = new Hono();
const facilitator = primerFacilitator();

const routes = {
  '/v1/*': {
    price: '$0.001',
    network: 'eip155:8453',
    payTo: '0xYourWalletAddress'
  }
};

app.use('/v1/*', paymentMiddleware(routes, { facilitator }));

API Reference

SKALE Networks

Network constants for SKALE chains:

import { skaleNetworks, skaleRpcUrls } from '@primersystems/x402';

// Network identifiers (CAIP-2 format)
skaleNetworks.base        // "eip155:1187947933"
skaleNetworks.baseSepolia // "eip155:324705682"

// RPC endpoints
skaleRpcUrls.base        // "https://skale-base.skalenodes.com/v1/base"
skaleRpcUrls.baseSepolia // "https://base-sepolia-testnet.skalenodes.com/v1/..."

Using SKALE Networks

import { skaleNetworks } from '@primersystems/x402';

const routes = {
  '/api/data': {
    price: '$0.001',
    network: skaleNetworks.base,
    payTo: '0xYourWalletAddress'
  }
};

Robinhood Chain

Network constants for Robinhood Chain (Arbitrum Orbit L2):

import { robinhoodNetworks, robinhoodRpcUrls } from '@primersystems/x402';

// Network identifiers (CAIP-2 format)
robinhoodNetworks.mainnet // "eip155:4663"
robinhoodNetworks.testnet // "eip155:46630"

// RPC endpoints
robinhoodRpcUrls.mainnet // "https://rpc.mainnet.chain.robinhood.com"
robinhoodRpcUrls.testnet // "https://rpc.testnet.chain.robinhood.com"

Using Robinhood Chain

import { robinhoodNetworks } from '@primersystems/x402';

const routes = {
  '/api/data': {
    price: '$0.001',
    network: robinhoodNetworks.mainnet,
    payTo: '0xYourWalletAddress'
  }
};

Prism Settlement

Prism enables gasless payments for any ERC-20 token via EIP-712 signatures. Use this for tokens that don't support EIP-3009 (like USDC does).

Creating Payment Payloads

import {
  createPrismPayload,
  getPrismNonce,
  PRISM_CONTRACT_ADDRESS,
  type PrismPaymentParams,
} from '@primersystems/x402';
import { createWalletClient, createPublicClient, http } from 'viem';
import { base } from 'viem/chains';
import { privateKeyToAccount } from 'viem/accounts';

// Set up viem clients
const account = privateKeyToAccount(process.env.PRIVATE_KEY as `0x${string}`);
const publicClient = createPublicClient({ chain: base, transport: http() });
const walletClient = createWalletClient({
  account,
  chain: base,
  transport: http()
});

// Create a signed payment payload
const payload = await createPrismPayload(walletClient, publicClient, {
  token: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913', // USDC on Base
  to: '0xRecipientAddress',
  value: 1000000n, // 1 USDC (6 decimals)
}, 'eip155:8453');

console.log(payload);
// {
//   x402Version: 2,
//   scheme: "exact",
//   network: "eip155:8453",
//   payload: {
//     signature: "0x...",
//     authorization: {
//       from: "0x...",
//       to: "0x...",
//       value: "1000000",
//       nonce: "0",
//       validAfter: 1234567890,
//       validBefore: 1234571490
//     }
//   }
// }

Prism API Reference

PrismPaymentParams

CLI

The CLI provides project scaffolding for Bittensor/Chutes AI proxies:

# Create a new Chutes AI proxy
npx @primersystems/x402 create chutes-proxy my-ai-api

# Navigate and install
cd my-ai-api
npm install

# Edit src/worker.ts to set your wallet address

# Set your Chutes API key
wrangler secret put CHUTES_API_KEY

# Run locally
npm run dev

# Deploy to Cloudflare Workers
npm run deploy

Generated Project Structure

my-ai-api/
  src/
    worker.ts      # Hono app with x402 middleware
  package.json     # Dependencies and scripts
  wrangler.toml    # Cloudflare Workers config
  tsconfig.json
  README.md
  .gitignore

Default Pricing

The generated proxy includes these endpoints: