From d82d2527af176cbd65eb8a80b9de43f34b374e85 Mon Sep 17 00:00:00 2001
From: markwallace-microsoft
 <127216156+markwallace-microsoft@users.noreply.github.com>
Date: Wed, 27 Aug 2025 14:40:31 +0100
Subject: [PATCH] Filter out reasoning response items during function calling

---
 ...ep03_OpenAIResponseAgent_ReasoningModel.cs | 23 +++++++++++++++++++
 .../OpenAI/Internal/ResponseThreadActions.cs  |  4 +++-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/dotnet/samples/GettingStartedWithAgents/OpenAIResponse/Step03_OpenAIResponseAgent_ReasoningModel.cs b/dotnet/samples/GettingStartedWithAgents/OpenAIResponse/Step03_OpenAIResponseAgent_ReasoningModel.cs
index a88059222efb..7db3ecc847bf 100644
--- a/dotnet/samples/GettingStartedWithAgents/OpenAIResponse/Step03_OpenAIResponseAgent_ReasoningModel.cs
+++ b/dotnet/samples/GettingStartedWithAgents/OpenAIResponse/Step03_OpenAIResponseAgent_ReasoningModel.cs
@@ -2,6 +2,7 @@
 using Microsoft.SemanticKernel;
 using Microsoft.SemanticKernel.Agents.OpenAI;
 using OpenAI.Responses;
+using Plugins;
 
 namespace GettingStarted.OpenAIResponseAgents;
 
@@ -80,4 +81,26 @@ exceed 80 columns
             WriteAgentChatMessage(responseItem);
         }
     }
+
+    [Fact]
+    public async Task UseOpenAIResponseAgentWithAReasoningModelAndToolsAsync()
+    {
+        // Define the agent
+        OpenAIResponseAgent agent = new(this.Client)
+        {
+            Name = "ResponseAgent",
+            Instructions = "Answer all queries with a detailed response.",
+        };
+
+        // Create a plugin that defines the tools to be used by the agent.
+        KernelPlugin plugin = KernelPluginFactory.CreateFromType<MenuPlugin>();
+        agent.Kernel.Plugins.Add(plugin);
+
+        // Invoke the agent and output the response
+        var responseItems = agent.InvokeAsync("What is the best value healthy meal?");
+        await foreach (ChatMessageContent responseItem in responseItems)
+        {
+            WriteAgentChatMessage(responseItem);
+        }
+    }
 }
diff --git a/dotnet/src/Agents/OpenAI/Internal/ResponseThreadActions.cs b/dotnet/src/Agents/OpenAI/Internal/ResponseThreadActions.cs
index a7c7cc0b8cc4..b5112c2ba808 100644
--- a/dotnet/src/Agents/OpenAI/Internal/ResponseThreadActions.cs
+++ b/dotnet/src/Agents/OpenAI/Internal/ResponseThreadActions.cs
@@ -57,7 +57,9 @@ internal static async IAsyncEnumerable<ChatMessageContent> InvokeAsync(
             }
             else
             {
-                inputItems.AddRange(response.OutputItems);
+                var filteredItems = response.OutputItems
+                    .Where(item => item is not ReasoningResponseItem); // Keep items that are not ReasoningResponseItem  
+                inputItems.AddRange(filteredItems);
             }
 
             var message = response.ToChatMessageContent();