Skip to main content

Smart account API reference

The following API methods are related to creating, managing, and signing with smart accounts.

aggregateSignature​

Aggregates multiple partial signatures into a single combined multisig signature.

Parameters​

NameTypeRequiredDescription
signaturesPartialSignature[]YesCollection of partial signatures provided by signers, to be merged into an aggregated signature.

Example​

import { 
  bundlerClient, 
  aliceSmartAccount, 
  bobSmartAccount,
  aliceAccount,
  bobAccount,
} from "./config.ts";
import { aggregateSignature } from "@metamask/delegation-toolkit";

const userOperation = await bundlerClient.prepareUserOperation({
  account: aliceSmartAccount,
  calls: [
    {
      target: zeroAddress,
      value: 0n,
      data: "0x",
    }
  ]
});

const aliceSignature = await aliceSmartAccount.signUserOperation(userOperation);
const bobSignature = await bobSmartAccount.signUserOperation(userOperation);

const aggregatedSignature = aggregateSignature({
  signatures: [{
    signer: aliceAccount.address,
    signature: aliceSignature,
    type: "ECDSA",
  }, {
    signer: bobAccount.address,
    signature: bobSignature,
    type: "ECDSA",
  }],
});

signDelegation​

Signs the delegation and returns the delegation signature.

Parameters​

NameTypeRequiredDescription
delegationOmit<Delegation, "signature">YesThe unsigned delegation object to sign.
chainIdnumberNoThe chain ID on which the Delegation Manager is deployed.

Example​

import { createDelegation } from "@metamask/delegation-toolkit";
import { delegatorSmartAccount } from "./config.ts";

// The address to which the delegation is granted. It can be an EOA address, or 
// smart account address.
const delegate = "0x2FcB88EC2359fA635566E66415D31dD381CF5585";

const delegation = createDelegation({
  to: delegate,
  from: account.address,
  // Empty caveats array - we recommend adding appropriate restrictions.
  caveats: [],
});

const signature = delegatorSmartAccount.signDelegation({ delegation });

signMessage​

Generates the EIP-191 signature using the MetaMaskSmartAccount signatory. The Delegation Toolkit uses Viem under the hood to provide this functionality.

Parameters​

See the Viem signMessage parameters.

Example​

import { smartAccount } from "./config.ts";

const signature = smartAccount.signMessage({
  message: 'hello world', 
})

signTypedData​

Generates the EIP-712 signature using the MetaMaskSmartAccount signatory. The Delegation Toolkit uses Viem under the hood to provide this functionality.

Parameters​

See the Viem signTypedData parameters.

Example​

import { smartAccount } from "./config.ts";

const signature = smartAccount.signTypedData({ 
  domain, 
  types, 
  primaryType: "Mail",
  message: { 
    from: { 
      name: "Cow",
      wallet: "0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826",
    }, 
    to: { 
      name: "Bob",
      wallet: "0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB",
    }, 
    contents: "Hello, Bob!",
  }, 
})

signUserOperation​

Signs a user operation with the MetaMaskSmartAccount signatory. The Delegation Toolkit uses Viem under the hood to provide this functionality.

Parameters​

See the Viem signUserOperation parameters.

Example​

import { smartAccount } from "./config.ts";

const userOpSignature = smartAccount.signUserOperation({ 
  callData: "0xdeadbeef",
  callGasLimit: 141653n,
  maxFeePerGas: 15000000000n,
  maxPriorityFeePerGas: 2000000000n,
  nonce: 0n,
  preVerificationGas: 53438n,
  sender: "0xE911628bF8428C23f179a07b081325cAe376DE1f",
  verificationGasLimit: 259350n,
  signature: "0x",
 });

toMetaMaskSmartAccount​

Creates a MetaMaskSmartAccount instance.

Parameters​

NameTypeRequiredDescription
clientClientYesViem Client to retrieve smart account data.
implementationTImplementationYesImplementation type for the smart account. Can be Hybrid or Multisig.
signatorySignatoryConfigByImplementation <TImplementation>YesSigners for the smart account. Can be a Viem Account, Viem Wallet Client, or a WebAuthnAccount. Web3AuthnAccounts are only supported for Hybrid implementations.
environmentDeleGatorEnvironmentNoEnvironment to resolve the smart contracts.
deployParamsDeployParams<TImplementation>Required if address is not providedThe parameters that will be used to deploy the smart account and generate its deterministic address.
deploySaltHexRequired if address is not providedThe salt that will be used to deploy the smart account.
addressAddressRequired if deployParams and deploySalt are not providedThe address of the smart account. If an address is provided, the smart account will not be deployed. This should be used if you intend to interact with an existing smart account.

Hybrid implementation example​

import {
  Implementation,
  toMetaMaskSmartAccount,
} from "@metamask/delegation-toolkit";
import { publicClient, account } from "./config.ts";

const smartAccount = await toMetaMaskSmartAccount({
  client: publicClient,
  implementation: Implementation.Hybrid,
  deployParams: [account.address, [], [], []],
  deploySalt: "0x",
  signatory: { account: account },
});

Multisig implementation example​

import { 
  publicClient, 
  aliceAccount, 
  bobAccount 
} from "./config.ts";
import { 
  Implementation, 
  toMetaMaskSmartAccount,
} from "@metamask/delegation-toolkit";

const signers = [ aliceAccount.address, bobAccount.address ];
const threshold = 2n

const aliceSmartAccount = await toMetaMaskSmartAccount({
  client: publicClient,
  implementation: Implementation.MultiSig,
  deployParams: [signers, threshold],
  deploySalt: "0x",
  signatory: [ { account: aliceAccount } ],
});
Last updated on by Ayush Bherwani