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MetaMask Connect options

When you create a MetaMask Connect client, pass configuration options to control how your dapp identifies itself, which networks it supports, and how connections behave. This page documents the available options for each client type.

Common options​

These options are available for all client types (createEVMClient, createSolanaClient, createMultichainClient).

dapp​

dapp: {
  name: string,
  url: string,
  iconUrl?: string,
}

Metadata about the dapp using MetaMask Connect.

  • name — Name of the dapp (required)
  • url — URL of the dapp (required)
  • iconUrl — URL of the dapp's icon (optional)
tip

Setting dapp metadata creates a clear and trustworthy user experience when connecting your dapp to MetaMask. MetaMask displays this metadata in the connection modal to help users identify and verify the connection request.

api.supportedNetworks​

api: {
  supportedNetworks: Record<string, string>
}

A map of network identifiers to RPC URLs for all networks your dapp supports. For the EVM client, use hex chain ID strings as keys (for example, '0x1' for Ethereum Mainnet, '0x89' for Polygon). For the multichain client, use CAIP-2 chain IDs (for example, 'eip155:1' for Ethereum Mainnet, 'solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp' for Solana Mainnet). For the Solana client, use friendly network names (mainnet, devnet, testnet) — the client converts these to CAIP-2 identifiers internally.

caution

Use Infura allowlists to protect against other people submitting requests to your API key. Restrict interactions to specific addresses, origins, user agents, and request methods.

getInfuraRpcUrls​

import { getInfuraRpcUrls } from '@metamask/connect-evm';

const urls = getInfuraRpcUrls('YOUR_INFURA_API_KEY');

A helper function exported from both @metamask/connect-evm and @metamask/connect-multichain. It returns a Record<string, string> of RPC URLs for all Infura-supported networks, keyed by chain identifier. Use it to populate api.supportedNetworks instead of manually constructing RPC URL maps:

api: {
  supportedNetworks: {
    ...getInfuraRpcUrls('YOUR_INFURA_API_KEY'),
    '0x89': 'https://polygon-rpc.com', // custom RPC for Polygon
  },
}

EVM client options​

Additional options available for createEVMClient.

ui​

ui: {
  headless?: boolean,
  preferExtension?: boolean,
  showInstallModal?: boolean,
}

Controls how the connection UI behaves:

  • headless — When true, the SDK emits a display_uri event but does not render any modal. You must render the QR code yourself. The default is false.
  • preferExtension — When true (default), the SDK uses the MetaMask browser extension via postMessage if installed. Set to false to force the MetaMask Wallet Protocol (MWP) QR/deeplink flow.
  • showInstallModal — When true (default), the SDK shows a modal prompting the user to install MetaMask if it is not detected.

mobile​

mobile: {
  preferredOpenLink?: (deeplink: string) => void,
  useDeeplink?: boolean,
}

Controls mobile-specific behavior:

  • preferredOpenLink — A function called to open a deeplink to MetaMask Mobile. Required for React Native (use (deeplink) => Linking.openURL(deeplink)). Without it, deeplinks fail silently and the connection flow hangs.
  • useDeeplink — When true, the SDK uses deeplinks for mobile connections.

eventHandlers​

eventHandlers: {
  display_uri?: (uri: string) => void,
  wallet_sessionChanged?: (session: any) => void,
  connect?: (info: { chainId: string, accounts: string[] }) => void,
  disconnect?: (error: { code: number, message: string }) => void,
  accountsChanged?: (accounts: string[]) => void,
  chainChanged?: (chainId: string) => void,
}

Register SDK-level event handlers during client creation. These are called in addition to any EIP-1193 provider event listeners:

  • display_uri — Fires during the connecting phase with the URI for QR code rendering. Register this when using ui.headless: true.
  • wallet_sessionChanged — Fires when a session is created, restored, or modified. Use this to detect session restoration on page reload.

You can also subscribe to these events after creation using client.on('display_uri', ...).

debug​

debug: boolean

Enables verbose console logging from the SDK internals. The default is false.

Full example​

import { createEVMClient, getInfuraRpcUrls } from '@metamask/connect-evm';

const client = await createEVMClient({
  dapp: {
    name: 'My EVM Dapp',
    url: 'https://mydapp.com',
    iconUrl: 'https://mydapp.com/icon.png',
  },
  api: {
    supportedNetworks: {
      ...getInfuraRpcUrls('YOUR_API_KEY'),
      '0x89': 'https://polygon-rpc.com',
    },
  },
  ui: {
    headless: false,
    preferExtension: true,
  },
  mobile: {
    preferredOpenLink: (deeplink) => window.open(deeplink, '_blank'),
  },
  eventHandlers: {
    display_uri: (uri) => console.log('QR URI:', uri),
    wallet_sessionChanged: (session) => console.log('Session:', session),
  },
  debug: false,
});

Wagmi connector​

MetaMask Connect provides a wagmi connector at @metamask/connect-evm/wagmi.

import { createConfig, http } from 'wagmi';
import { mainnet, sepolia } from 'wagmi/chains';
import { metaMask } from '@metamask/connect-evm/wagmi';

export const wagmiConfig = createConfig({
  chains: [mainnet, sepolia],
  connectors: [
    metaMask({
      dapp: {
        name: 'My DApp',
        url: typeof window !== 'undefined' ? window.location.href : undefined,
      },
    }),
  ],
  transports: {
    [mainnet.id]: http(),
    [sepolia.id]: http(),
  },
});

The connector ID is 'metaMaskSDK'. Find it with connectors.find(c => c.id === 'metaMaskSDK'). All standard wagmi hooks (useConnect, useAccount, useDisconnect, etc.) work unchanged.

The metaMask() function accepts the same dapp, mobile, and debug options as createEVMClient.

Solana client options​

Additional options available for createSolanaClient.

skipAutoRegister​

skipAutoRegister: boolean

Skips automatically registering MetaMask with the Wallet Standard registry when the client is created. The default is false, meaning MetaMask is registered automatically and appears as a wallet option in any dapp using @solana/wallet-adapter.

Set to true if you want to control when registration happens by calling registerWallet() manually.

Full example​

import { createSolanaClient } from '@metamask/connect-solana';

const client = await createSolanaClient({
  dapp: {
    name: 'My Solana Dapp',
    url: 'https://mydapp.com',
    iconUrl: 'https://mydapp.com/icon.png',
  },
  api: {
    supportedNetworks: {
      mainnet: 'https://api.mainnet-beta.solana.com',
      devnet: 'https://api.devnet.solana.com',
    },
  },
});

Multichain client options​

Additional options available for createMultichainClient.

Singleton behavior

createMultichainClient returns a single shared instance per global context. Calling it a second time with different options merges the new api.supportedNetworks, ui.*, mobile.*, transport.extensionId, and debug values into the existing instance rather than creating a new one. The dapp value is never overwritten on subsequent calls.

Full example​

import { createMultichainClient } from '@metamask/connect-multichain';

const client = await createMultichainClient({
  dapp: {
    name: 'My Multichain Dapp',
    url: 'https://mydapp.com',
    iconUrl: 'https://mydapp.com/icon.png',
  },
  api: {
    supportedNetworks: {
      'eip155:1': 'https://mainnet.infura.io/v3/YOUR_API_KEY',
      'eip155:137': 'https://polygon-mainnet.infura.io/v3/YOUR_API_KEY',
      'solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp': 'https://api.mainnet-beta.solana.com',
    },
  },
});

Legacy options​

The following options are from the previous MetaMask SDK and may still be supported for backwards compatibility.

Legacy options reference

checkInstallationImmediately​

checkInstallationImmediately: boolean

Enables or disables immediately checking if MetaMask is installed on the user's browser. The default is false.

checkInstallationOnAllCalls​

checkInstallationOnAllCalls: boolean

Enables or disables checking if MetaMask is installed before each RPC request. The default is false.

communicationServerUrl​

communicationServerUrl: string

The URL of the communication server to use. This option is mainly used for debugging and testing.

dappMetadata​

dappMetadata: {
  name: string,
  url: string,
  iconUrl?: string,
}

Legacy equivalent of dapp. Metadata about the dapp using MetaMask Connect.

enableAnalytics​

enableAnalytics: boolean

Enables or disables sending anonymous analytics to MetaMask. The default is true.

extensionOnly​

extensionOnly: boolean

Enables or disables automatically using the MetaMask browser extension if detected. The default is true.

infuraAPIKey​

infuraAPIKey: string

The Infura API key to use for RPC requests.

headless​

headless: boolean

Enables or disables headless mode for custom modals. The default is false.

openDeeplink: (link: string) => void

A function called to open a deeplink to the MetaMask mobile app.

readonlyRPCMap​

readonlyRPCMap: Record<string, string>

A map of chain IDs to RPC URLs for read-only requests.

shouldShimWeb3​

shouldShimWeb3: boolean

Enables or disables shimming the window.web3 object. The default is true.

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