Core SDK — EIP-1193 Provider

CROSSx SDK provides a standard EIP-1193 compatible Ethereum provider. This allows seamless integration with popular Web3 libraries such as ethers.js, viem, and web3.js.

What is EIP-1193?

EIP-1193 defines a standard JavaScript API for Ethereum providers. Any library that accepts an EIP-1193 provider (like MetaMask's window.ethereum) can also work with the CROSSx provider — no code changes needed.

Getting the provider

const provider = sdk.getProvider('eip155:612044')

The chainId parameter must be in CAIP-2 format (e.g. eip155:612044).

Supported RPC methods

The CROSSx provider supports the following JSON-RPC methods:

Method	Description
`eth_accounts`	Returns connected wallet addresses
`eth_chainId`	Returns the chain ID (hex)
`eth_blockNumber`	Returns the latest block number
`eth_getBalance`	Returns account balance
`eth_getTransactionCount`	Returns account nonce
`eth_call`	Executes a read-only contract call
`eth_estimateGas`	Estimates gas for a transaction
`eth_gasPrice`	Returns current gas price
`eth_getTransactionReceipt`	Returns transaction receipt
`personal_sign`	Signs a message (opens confirmation modal)
`eth_sign`	Signs a message (opens confirmation modal)
`eth_signTypedData`	Signs EIP-712 typed data (opens confirmation modal)
`eth_signTypedData_v3`	Signs EIP-712 typed data v3 (opens confirmation modal)
`eth_signTypedData_v4`	Signs EIP-712 typed data v4 (opens confirmation modal)
`eth_sendTransaction`	Signs and sends a transaction (opens confirmation modal)
`wallet_switchEthereumChain`	Switches the active chain
`wallet_addEthereumChain`	Acknowledged (no-op)
`net_version`	Returns the network version string

::: warning Read-only methods execute immediately. Signing and sending methods always display a user confirmation modal. :::

Integration with ethers.js v6

import { BrowserProvider } from 'ethers'

const provider = sdk.getProvider('eip155:612044')
const ethersProvider = new BrowserProvider(provider)

// Read-only operations
const blockNumber = await ethersProvider.getBlockNumber()
const balance = await ethersProvider.getBalance('0xYourAddress')

// Get signer for write operations
const signer = await ethersProvider.getSigner()
const address = await signer.getAddress()

// Sign message
const signature = await signer.signMessage('Hello CROSSx')

// Send transaction
const tx = await signer.sendTransaction({
  to: '0xRecipient...',
  value: ethers.parseEther('0.1'),
})
const receipt = await tx.wait()
console.log('TX mined:', receipt.hash)

Integration with ethers.js v5

import { ethers } from 'ethers'

const provider = sdk.getProvider('eip155:612044')
const ethersProvider = new ethers.providers.Web3Provider(provider)

const signer = ethersProvider.getSigner()
const address = await signer.getAddress()
const balance = await ethersProvider.getBalance(address)

// Send transaction
const tx = await signer.sendTransaction({
  to: '0xRecipient...',
  value: ethers.utils.parseEther('0.1'),
})
await tx.wait()

Integration with viem

import { createPublicClient, createWalletClient, custom, parseEther } from 'viem'

const provider = sdk.getProvider('eip155:612044')

// Public client (read-only)
const publicClient = createPublicClient({
  transport: custom(provider),
})

const blockNumber = await publicClient.getBlockNumber()
const balance = await publicClient.getBalance({
  address: '0xYourAddress',
})

// Wallet client (read + write)
const walletClient = createWalletClient({
  transport: custom(provider),
})

const [address] = await walletClient.getAddresses()

// Sign message
const signature = await walletClient.signMessage({
  account: address,
  message: 'Hello CROSSx',
})

// Send transaction
const hash = await walletClient.sendTransaction({
  account: address,
  to: '0xRecipient...',
  value: parseEther('0.1'),
})

Integration with web3.js

import Web3 from 'web3'

const provider = sdk.getProvider('eip155:612044')
const web3 = new Web3(provider)

const accounts = await web3.eth.getAccounts()
const balance = await web3.eth.getBalance(accounts[0])

// Send transaction
const receipt = await web3.eth.sendTransaction({
  from: accounts[0],
  to: '0xRecipient...',
  value: web3.utils.toWei('0.1', 'ether'),
})

Contract interaction

Read contract (ethers.js)

const provider = sdk.getProvider('eip155:612044')
const ethersProvider = new BrowserProvider(provider)

const erc20 = new ethers.Contract('0xTokenAddress', [
  'function name() view returns (string)',
  'function symbol() view returns (string)',
  'function balanceOf(address) view returns (uint256)',
], ethersProvider)

const name = await erc20.name()
const balance = await erc20.balanceOf('0xYourAddress')

Write contract (ethers.js)

const signer = await ethersProvider.getSigner()

const erc20 = new ethers.Contract('0xTokenAddress', [
  'function transfer(address to, uint256 amount) returns (bool)',
], signer)

const tx = await erc20.transfer('0xRecipient', ethers.parseUnits('100', 18))
const receipt = await tx.wait()

Contract interaction (viem)

import { createPublicClient, createWalletClient, custom, parseUnits } from 'viem'
import { erc20Abi } from 'viem'

const provider = sdk.getProvider('eip155:612044')

const publicClient = createPublicClient({ transport: custom(provider) })
const walletClient = createWalletClient({ transport: custom(provider) })

// Read
const balance = await publicClient.readContract({
  address: '0xTokenAddress',
  abi: erc20Abi,
  functionName: 'balanceOf',
  args: ['0xYourAddress'],
})

// Write
const [account] = await walletClient.getAddresses()
const hash = await walletClient.writeContract({
  account,
  address: '0xTokenAddress',
  abi: erc20Abi,
  functionName: 'transfer',
  args: ['0xRecipient', parseUnits('100', 18)],
})

Event listening

The CROSSx provider emits standard EIP-1193 events:

const provider = sdk.getProvider('eip155:612044')

provider.on('accountsChanged', (accounts: string[]) => {
  console.log('Accounts changed:', accounts)
})

provider.on('chainChanged', (chainId: string) => {
  console.log('Chain changed:', chainId)
})

provider.on('disconnect', () => {
  console.log('Disconnected')
})

Using with multiple chains

const crossProvider = sdk.getProvider('eip155:612044')
const ethProvider = sdk.getProvider('eip155:1')
const polygonProvider = sdk.getProvider('eip155:137')

// Each provider routes RPC calls to the correct chain
const crossBalance = await new BrowserProvider(crossProvider).getBalance(address)
const ethBalance = await new BrowserProvider(ethProvider).getBalance(address)

Raw RPC request

For methods not covered by library abstractions, use the provider's request method directly:

const provider = sdk.getProvider('eip155:612044')

// Any JSON-RPC method
const result = await provider.request({
  method: 'eth_getBlockByNumber',
  params: ['latest', false],
})