new doc draft

Author: PatrickFarley

articles/ai-services/openai/how-to/model-router.md

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+---
+title: How to use model router in Azure OpenAI Service
+titleSuffix: Azure OpenAI Service
+description: Learn how to use the model router in Azure OpenAI Service to select the best model for your task.
+author: PatrickFarley
+ms.author: pafarley 
+#customer intent: 
+ms.service: azure-ai-openai
+ms.topic: how-to
+ms.date: 04/17/2025
+manager: nitinme
+---
+
+# Use model router
+
+Azure OpenAI model router is a deployable AI chat model that automatically selects the best underlying chat model to respond to a given prompt. It uses a combination of preexisting models to provide high performance while saving on compute costs where possible. For more information on how model router works and its advantages and limitations, see the [Model router concepts guide](../concepts/model-router.md).
+
+You can access model router through the Completions API just as you would use a single base model like GPT-4.
+
+## Deploy a model router model
+
+Model router is packaged as a single OpenAI model that you deploy. Follow the steps in the [resource deployment guide](/azure/ai-services/openai/how-to/create-resource), and in the **Create new deployment** step, find `Azure OpenAI model router` in the **Model** list. Select it, and then complete the rest of the deployment steps.
+
+> [!NOTE]
+> You don't need to deploy the underlying models separately. Model router works independently of your other deployed models.
+
+## Use model router in chat
+
+### REST API
+
+
+### Portal 
+
+## Evaluate model router performance
+
+## Troubleshooting