update docs

Author: mattgotteiner

README.md

@@ -256,6 +256,7 @@ You can find extensive documentation in the [docs](docs/README.md) folder:
     - [All features](docs/deploy_features.md)
     - [Login and access control](docs/login_and_acl.md)
     - [GPT-4 Turbo with Vision](docs/gpt4v.md)
+    - [Reasoning](docs/reasoning.md)
     - [Private endpoints](docs/deploy_private.md)
   - [Sharing deployment environments](docs/sharing_environments.md)
 - [Local development](docs/localdev.md)

docs/images/reasoning.png

@@ -0,0 +1,48 @@
+# RAG chat: Using reasoning models
+
+This repository includes an optional feature that uses reasoning models to generate responses based on retrieved content. These models spend more time processing and understanding the user's request.
+
+## Using the feature
+
+### Supported Models
+
+* o3-mini
+* o1
+
+### Prerequisites
+
+* The ability to deploy a reasoning model in the [supported regions](https://learn.microsoft.com/azure/ai-services/openai/concepts/models#standard-deployment-model-availability). If you're not sure, try to create a o3-mini deployment from your Azure OpenAI deployments page.
+
+### Deployment
+
+1. **Enable reasoning:**
+
+   Set the environment variables for your Azure OpenAI GPT deployments to your reasoning model
+
+   ```shell
+   azd env set AZURE_OPENAI_CHATGPT_MODEL o3-mini
+   azd env set AZURE_OPENAI_CHATGPT_DEPLOYMENT o3-mini
+   ```
+
+2. **(Optional) Set default reasoning effort**
+
+   You can configure how much effort the reasoning model spends on processing and understanding the user's request. Valid options are `low`, `medium`, and `high`. Reasoning effort defaults to `medium` if not set.
+
+   Set the environment variable for reasoning effort
+
+   ```shell
+   azd env set AZURE_OPENAI_REASONING_EFFORT medium
+   ```
+
+3. **Clean old deployments (optional):**
+   Run `azd down --purge` for a fresh setup.
+
+4. **Start the application:**
+   Execute `azd up` to build, provision, deploy, and initiate document preparation.
+
+5. **Try out the feature:**
+    ![Reasoning configuration screenshot](./images/reasoning.png)
+    ![Thought process token usage](./images/token-usage.png)
+   * Access the developer options in the web app and change "Reasoning Effort".
+   * Token usage is visible in the thought process tab
+