[BREAKING] Update OpenAI SDK to 2.9.1

dotnet/Directory.Packages.props

@@ -35,7 +35,7 @@
     <!-- System.* -->
     <PackageVersion Include="Microsoft.Bcl.AsyncInterfaces" Version="10.0.3" />
     <PackageVersion Include="Microsoft.Bcl.HashCode" Version="6.0.0" />
-    <PackageVersion Include="System.ClientModel" Version="1.8.1" />
+    <PackageVersion Include="System.ClientModel" Version="1.9.0" />
     <PackageVersion Include="System.CodeDom" Version="10.0.0" />
     <PackageVersion Include="System.Collections.Immutable" Version="10.0.1" />
     <PackageVersion Include="System.CommandLine" Version="2.0.0-rc.2.25502.107" />
@@ -109,7 +109,7 @@
     <PackageVersion Include="AWSSDK.Extensions.Bedrock.MEAI" Version="4.0.5.1" />
     <PackageVersion Include="Microsoft.ML.OnnxRuntimeGenAI" Version="0.10.0" />
     <PackageVersion Include="OllamaSharp" Version="5.4.8" />
-    <PackageVersion Include="OpenAI" Version="2.8.0" />
+    <PackageVersion Include="OpenAI" Version="2.9.1" />
     <!-- Identity -->
     <PackageVersion Include="Microsoft.Identity.Client.Extensions.Msal" Version="4.78.0" />
     <!-- Workflows -->

dotnet/samples/02-agents/AgentProviders/Agent_With_OpenAIResponses/Program.cs

@@ -3,6 +3,7 @@
 // This sample shows how to create and use a simple AI agent with OpenAI Responses as the backend.
 
 using Microsoft.Agents.AI;
+using Microsoft.Extensions.AI;
 using OpenAI;
 using OpenAI.Responses;
 
@@ -11,8 +12,17 @@
 
 AIAgent agent = new OpenAIClient(
     apiKey)
-     .GetResponsesClient(model)
-     .AsAIAgent(instructions: "You are good at telling jokes.", name: "Joker");
+     .GetResponsesClient()
+     .AsAIAgent(
+        new ChatClientAgentOptions()
+        {
+            Name = "Joker",
+            ChatOptions = new ChatOptions()
+            {
+                ModelId = model,
+                Instructions = "You are good at telling jokes."
+            }
+        });
 
 // Invoke the agent and output the text result.
 Console.WriteLine(await agent.RunAsync("Tell me a joke about a pirate."));

dotnet/samples/02-agents/AgentWithOpenAI/Agent_OpenAI_Step02_Reasoning/Program.cs

@@ -10,10 +10,11 @@
 var model = Environment.GetEnvironmentVariable("OPENAI_CHAT_MODEL_NAME") ?? "gpt-5";
 
 var client = new OpenAIClient(apiKey)
-        .GetResponsesClient(model)
+        .GetResponsesClient()
         .AsIChatClient().AsBuilder()
         .ConfigureOptions(o =>
         {
+            o.ModelId = model;
             o.Reasoning = new()
             {
                 Effort = ReasoningEffort.Medium,

dotnet/samples/02-agents/AgentWithOpenAI/Agent_OpenAI_Step04_CreateFromOpenAIResponseClient/Program.cs

@@ -2,6 +2,8 @@
 
 // This sample demonstrates how to create OpenAIResponseClientAgent directly from an ResponsesClient instance.
 
+using Microsoft.Agents.AI;
+using Microsoft.Extensions.AI;
 using OpenAI;
 using OpenAI.Responses;
 using OpenAIResponseClientSample;
@@ -10,10 +12,18 @@
 var model = Environment.GetEnvironmentVariable("OPENAI_CHAT_MODEL_NAME") ?? "gpt-4o-mini";
 
 // Create a ResponsesClient directly from OpenAIClient
-ResponsesClient responseClient = new OpenAIClient(apiKey).GetResponsesClient(model);
+ResponsesClient responseClient = new OpenAIClient(apiKey).GetResponsesClient();
 
 // Create an agent directly from the ResponsesClient using OpenAIResponseClientAgent
-OpenAIResponseClientAgent agent = new(responseClient, instructions: "You are good at telling jokes.", name: "Joker");
+OpenAIResponseClientAgent agent = new(responseClient, new ChatClientAgentOptions()
+{
+    Name = "Joker",
+    ChatOptions = new ChatOptions()
+    {
+        ModelId = model,
+        Instructions = "You are good at telling jokes."
+    }
+});
 
 ResponseItem userMessage = ResponseItem.CreateUserMessageItem("Tell me a joke about a pirate.");
 

dotnet/samples/02-agents/AgentWithOpenAI/Agent_OpenAI_Step05_Conversation/Program.cs

@@ -22,7 +22,16 @@
 ConversationClient conversationClient = openAIClient.GetConversationClient();
 
 // Create an agent directly from the ResponsesClient using OpenAIResponseClientAgent
-ChatClientAgent agent = new(openAIClient.GetResponsesClient(model).AsIChatClient(), instructions: "You are a helpful assistant.", name: "ConversationAgent");
+ChatClientAgent agent = new(openAIClient.GetResponsesClient().AsIChatClient(),
+    new ChatClientAgentOptions()
+    {
+        Name = "ConversationAgent",
+        ChatOptions = new ChatOptions()
+        {
+            ModelId = model,
+            Instructions = "You are a helpful assistant."
+        }
+    });
 
 ClientResult createConversationResult = await conversationClient.CreateConversationAsync(BinaryContent.Create(BinaryData.FromString("{}")));
 

dotnet/samples/05-end-to-end/AgentWebChat/AgentWebChat.Web/OpenAIResponsesAgentClient.cs

@@ -27,9 +27,10 @@ public override async IAsyncEnumerable<AgentResponseUpdate> RunStreamingAsync(
             Transport = new HttpClientPipelineTransport(httpClient)
         };
 
-        var openAiClient = new ResponsesClient(model: agentName, credential: new ApiKeyCredential("dummy-key"), options: options).AsIChatClient();
+        var openAiClient = new ResponsesClient(credential: new ApiKeyCredential("dummy-key"), options: options).AsIChatClient();
         var chatOptions = new ChatOptions()
         {
+            ModelId = agentName,
             ConversationId = sessionId
         };