@type t() :: %ApolloSignal.Types.BatchSendItemResponse{
  created_at: String.t() | nil,
  error: String.t() | nil,
  id: String.t() | nil,
  index: integer(),
  message_id: String.t() | nil,
  scheduled_at: String.t() | nil,
  status: String.t() | nil
}