anchor.diff:          steps => [string],
           %% Total number of steps to be executed.
           totalSteps => integer,
  -        %% The name of an error type.
  -        error => {string, optional},
  -        %% The detailed error description.
  -        description => {string, optional},
  -        %% The name of a module containing function that returned error.
  -        module => {string, optional},
  -        %% The name of a function that returned error.
  -        function => {string, optional},
  -        %% The collection of hosts with associated error description.
  -        hosts => {#{'_' => error_model()}, optional}
  +        error => {error_model(), optional}
       }.
   
   %%--------------------------------------------------------------------
  
positive.code:     provider_storages_model/0,
      remote_provider_details_model/0,
      service_databases_model/0,
      service_error_model/0,
      service_hosts_model/0,
      service_status_model/0,
      service_status_host_model/0,
  
negative.code:     }.
  
  %%--------------------------------------------------------------------
  %% @doc The service hosts configuration.
  %% @end
  %%--------------------------------------------------------------------
  