Azure AI Model Inference: deprecation guidance to OpenAI

sdk/ai/Azure.AI.Inference/MIGRATION.md

@@ -0,0 +1,97 @@
+## Migrate from `Azure.AI.Inference` to `OpenAI`
+
+Following the `2025-05-01-preview` service API version, Model Inference has converged its capabilities with OpenAI-compatible API surfaces available with Azure AI Foundry. As part of this convergence, the `Azure.AI.Inference` library is discontinued in favor of support via the official `OpenAI` library.
+
+This document describes the migration steps from common model inference scenarios to equivalent OpenAI operations.
+
+## Client configuration
+
+**Before, using `Azure.AI.Inference`:**
+
+```csharp
+using Azure.AI.Inference;
+
+Uri endpoint = new(Environment.GetEnvironmentVariable("AZURE_AI_CHAT_ENDPOINT"));
+AzureKeyCredential credential = new(System.Environment.GetEnvironmentVariable("AZURE_AI_CHAT_KEY"));
+
+// Chat
+ChatCompletionsClient client = new(endpoint, credential);
+
+// Embeddings
+EmbeddingsClient embeddingsClient = new(endpoint, credential, new AzureAIInferenceClientOptions());
+```
+
+**After, using `OpenAI`:**
+
+```csharp
+using OpenAI.Chat;
+
+Uri endpoint = new($"{Environment.GetEnvironmentVariable("AI_FOUNDRY_ENDPOINT")}/openai/v1"));
+ApiKeyCredential credential = new(Environment.GetEnvironmentVariable("AI_FOUNDRY_API_KEY"));
+OpenAIClient openAIClient = new(
+    credential,
+    new OpenAIClientOptions()
+    {
+        Endpoint = endpoint,
+    });
+
+// Chat
+ChatClient client = openAIClient.GetChatClient(Environment.GetEnvironmentVariable("AI_FOUNDRY_MODEL_DEPLOYMENT"));
+
+// Embeddings
+EmbeddingClient embeddingClient = openAIClient.GetEmbeddingClient(Environment.GetEnvironmentVariable("AI_FOUNDRY_MODEL_DEPLOYMENT"));
+```
+
+## Use Chat Completions
+
+**Before, with `Azure.AI.Inference`:**
+
+```csharp
+Response<ChatCompletions> response = client.Complete(
+    new ChatCompletionsOptions()
+    {
+        Messages =
+        {
+            new ChatRequestSystemMessage("You are a helpful assistant."),
+            new ChatRequestUserMessage("How many feet are in a mile?"),
+        }
+    });
+Console.WriteLine(response.Value.Content);
+```
+
+**After, with `OpenAI`:**
+
+```csharp
+ChatCompletion completion = client.CompleteChat(
+    [
+        new SystemChatMessage("You are a helpful assistant."),
+        new UserChatMessage("How many feet are in a mile?"),
+    ]);
+Console.WriteLine(completion.Content[0].Text);
+```
+
+## Use Text Embeddings
+
+**Before, with `Azure.AI.Inference`:**
+
+```csharp
+EmbeddingsOptions options = new(
+    new List<string> { "King", "Queen", "Jack", "Page" });
+Response<EmbeddingsResult> response = client.Embed(options);
+foreach (EmbeddingItem item in response.Value.Data)
+{
+    List<float> embedding = item.Embedding.ToObjectFromJson<List<float>>();
+    Console.WriteLine($"Index: {item.Index}, Embedding: <{string.Join(", ", embedding)}>");
+}
+```
+
+**After, with `OpenAI`:**
+
+```csharp
+OpenAIEmbedding embedding = client.GenerateEmbedding(["King", "Queen", "Jack", "Page"]);
+
+foreach (float embeddingValue in embedding.ToFloats())
+{
+    Console.WriteLine(embeddingValue);
+}
+```

sdk/ai/Azure.AI.Inference/README.md

@@ -1,5 +1,8 @@
 # Azure Inference client library for .NET
 
+> [!NOTE]
+> The `Azure.AI.Inference` library is now deprecated. Going forward, the official `OpenAI` library is the successor to this package. For more details, see [the migration guide](MIGRATION.md).
+
 The client library (in preview) does inference, including chat completions, for AI models deployed by [Azure AI Foundry](https://ai.azure.com) and [Azure Machine Learning Studio](https://ml.azure.com/). It supports Serverless API endpoints and Managed Compute endpoints (formerly known as Managed Online Endpoints). The client library makes services calls using REST API version `2024-05-01-preview`, as documented in [Azure AI Model Inference API](https://learn.microsoft.com/azure/ai-studio/reference/reference-model-inference-api). For more information see [Overview: Deploy AI models in Azure AI Foundry portal](https://learn.microsoft.com/azure/ai-studio/concepts/deployments-overview).
 
 Use the model inference client library to: