| ### MutateConversionCustomVariables | |---| | `` rpc MutateConversionCustomVariables(`https://developers.google.com/google-ads/api/reference/rpc/v25/MutateConversionCustomVariablesRequest`) returns (`https://developers.google.com/google-ads/api/reference/rpc/v25/MutateConversionCustomVariablesResponse`) `` Creates or updates conversion custom variables. Operation statuses are returned. List of thrown errors: [AuthenticationError](https://developers.google.com/google-ads/api/reference/rpc/v25/AuthenticationErrorEnum.AuthenticationError) [AuthorizationError](https://developers.google.com/google-ads/api/reference/rpc/v25/AuthorizationErrorEnum.AuthorizationError) [ConversionCustomVariableError](https://developers.google.com/google-ads/api/reference/rpc/v25/ConversionCustomVariableErrorEnum.ConversionCustomVariableError) [DatabaseError](https://developers.google.com/google-ads/api/reference/rpc/v25/DatabaseErrorEnum.DatabaseError) [HeaderError](https://developers.google.com/google-ads/api/reference/rpc/v25/HeaderErrorEnum.HeaderError) [InternalError](https://developers.google.com/google-ads/api/reference/rpc/v25/InternalErrorEnum.InternalError) [QuotaError](https://developers.google.com/google-ads/api/reference/rpc/v25/QuotaErrorEnum.QuotaError) [RequestError](https://developers.google.com/google-ads/api/reference/rpc/v25/RequestErrorEnum.RequestError) [Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v25/services/conversion_custom_variable_service.proto) | Authorization scopes : Requires the following OAuth scope: - `https://www.googleapis.com/auth/adwords` For more information, see the [OAuth 2.0 Overview](https://developers.google.com/identity/protocols/OAuth2).