> ## Documentation Index
> Fetch the complete documentation index at: https://daehan-base.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# wallet_addEthereumChain

> Add a new Ethereum chain to the wallet

Defined in [EIP-3085](https://eips.ethereum.org/EIPS/eip-3085)

<Info>
  Requests that the wallet tracks the given chain and adds it to the wallet's UI. This method is used to suggest new networks to the user.
</Info>

## Parameters

<ParamField body="chainData" type="object" required>
  The chain data object containing network information.

  <Expandable title="Chain data properties">
    <ParamField body="chainId" type="string" required>
      A 0x-prefixed hexadecimal string representing the chain ID.
    </ParamField>

    <ParamField body="chainName" type="string" required>
      The human-readable name of the chain.
    </ParamField>

    <ParamField body="nativeCurrency" type="object" required>
      An object describing the currency that is "native" to this chain.

      <Expandable title="Native currency properties">
        <ParamField body="name" type="string" required>
          The name of the native currency.
        </ParamField>

        <ParamField body="symbol" type="string" required>
          The symbol of the native currency.
        </ParamField>

        <ParamField body="decimals" type="number" required>
          The number of decimals for the native currency.
        </ParamField>
      </Expandable>
    </ParamField>

    <ParamField body="rpcUrls" type="array" required>
      An array of RPC URL strings.
    </ParamField>

    <ParamField body="blockExplorerUrls" type="array">
      An array of block explorer URL strings (optional).
    </ParamField>

    <ParamField body="iconUrls" type="array">
      An array of icon URL strings (optional).
    </ParamField>
  </Expandable>
</ParamField>

## Returns

<ResponseField name="result" type="null">
  Returns null if successful.
</ResponseField>

<RequestExample>
  ```json Request theme={null}
  {
    "id": 1,
    "jsonrpc": "2.0",
    "method": "wallet_addEthereumChain",
    "params": [{
      "chainId": "0x2105",
      "chainName": "Base Mainnet",
      "nativeCurrency": {
        "name": "Ether",
        "symbol": "ETH",
        "decimals": 18
      },
      "rpcUrls": ["https://mainnet.base.org"],
      "blockExplorerUrls": ["https://basescan.org"]
    }]
  }
  ```
</RequestExample>

<ResponseExample>
  ```json Success Response theme={null}
  {
    "id": 1,
    "jsonrpc": "2.0",
    "result": null
  }
  ```
</ResponseExample>

## Error Handling

| Code | Message                        | Description                               |
| ---- | ------------------------------ | ----------------------------------------- |
| 4001 | User rejected the request      | User denied adding the chain              |
| 4100 | Requested method not supported | The method is not supported by the wallet |
| 4902 | Unrecognized chain ID          | The chain ID is not recognized            |

<Warning>
  Make sure to provide accurate RPC URLs and block explorer URLs. Incorrect URLs may cause connectivity issues.
</Warning>