> ## Documentation Index > Fetch the complete documentation index at: https://openrouter.ai/docs/llms.txt > Use this file to discover all available pages before exploring further. # RoutedServiceTier The service tier this request was routed to (e.g. flex, priority). The tier actually applied and billed is determined by the provider response and may differ. ## Example Usage ```typescript theme={null} import { RoutedServiceTier } from "@openrouter/sdk/models"; let value: RoutedServiceTier = "priority"; // Open enum: unrecognized values are captured as Unrecognized ``` ## Values ```typescript theme={null} "flex" | "priority" | Unrecognized ```