MetaMask
Multichain API
wallet_addEthereumChain
Summary: Adds an Ethereum chain to the wallet.
Creates a confirmation asking the user to add the specified chain to the wallet application. The caller must specify a chain ID and some chain metadata. The wallet application may refuse or accept the request.
null
is returned if the chain is added, and an error otherwise. Introduced by EIP-3085.
Parameters
AddEthereumChainParameter object
requiredAddEthereumChainParameter
Returns
AddEthereumChainResult null
Errors
Code
Message
-32602
Expected null or array with at least one valid string HTTPS URL 'blockExplorerUrl'. Received: ${blockExplorerUrls}
-32602
Expected 0x-prefixed, unpadded, non-zero hexadecimal string 'chainId'. Received:
${chainId}
-32602
Invalid chain ID "${_chainId}": numerical value greater than max safe value. Received:
${chainId}
-32602
May not specify default MetaMask chain.
-32602
Expected 2-6 character string 'nativeCurrency.symbol'. Received:
${ticker}
-32602
nativeCurrency.symbol does not match currency symbol for a network the user already has added with the same chainId. Received:
${ticker}
Customize request
Parameter
Value
Connect your MetaMask wallet to run requests successfully.
Request
await window.ethereum.request({
"method": "wallet_addEthereumChain",
"params": [
{
chainId: "0x64",
chainName: "Gnosis",
rpcUrls: [
"https://rpc.gnosischain.com"
],
iconUrls: [
"https://xdaichain.com/fake/example/url/xdai.svg",
"https://xdaichain.com/fake/example/url/xdai.png"
],
nativeCurrency: {
name: "XDAI",
symbol: "XDAI",
decimals: 18
},
blockExplorerUrls: [
"https://blockscout.com/poa/xdai/"
]
}
],
});
Example response
null