wallet_addEthereumChain
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.
Params
(1)1. AddEthereumChainParameter (required)
MUST specify the integer ID of the chain as a hexadecimal string, per the eth_chainId Ethereum RPC method. The wallet SHOULD compare the specified chain ID value with the eth_chainId return value from the endpoint. If these values aren't identical, the wallet MUST reject the request.
If provided, MUST specify one or more URLs pointing to block explorer sites for the chain.
If provided, MUST specify a human-readable name for the chain.
If provided, MUST specify one or more URLs pointing to reasonably sized images that can be used to visually identify the chain.
If provided, MUST describe the native currency of the chain using the name, symbol, and decimals fields.
A non-negative integer.
SHOULD be human-readable.
SHOULD be human-readable.
Result
(AddEthereumChainResult)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} |
Example
Request
await window.ethereum.request({
"method": "wallet_addEthereumChain",
"params": [
{
"chainId": "0x64",
"chainName": "Gnosis",
"rpcUrls": [
"https://rpc.ankr.com/gnosis"
],
"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/"
]
}
]
});
Result
"null"