# evmAuth · FT4 TypeScript client · Chromia Docs (concept)

> evmAuth(
    accountId: BufferId,
    authDescriptorId: BufferId,
    signatures: ( Signature | null)[],
): Operation Creates a ft4.evm_auth operation obje

Source: https://docs.chromia.com/pages/ft4-ts-client/functions/authentication.evmAuth/

Function

# evmAuth

* ```signature
  evmAuth(
      accountId: BufferId,
      authDescriptorId: BufferId,
      signatures: (Signature | null)[],
  ): Operation
  ```

  Creates a `ft4.evm_auth` operation object from the provided data

  #### Parameters

  + accountId: BufferId

    the account id to authorize for
  + authDescriptorId: BufferId

    the auth descriptor to authorize with
  + signatures: ([Signature](https://docs.chromia.com/pages/ft4-ts-client/types/authentication.Signature/) | null)[]

    signatures performed by the keys stored in the auth descriptor

  #### Returns Operation

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-ts-client/functions/authentication.evmAuth.html)Generated API reference, mirrored from the live docs