diff --git a/Anthropic.SDK.Tests/Anthropic.SDK.Tests.csproj b/Anthropic.SDK.Tests/Anthropic.SDK.Tests.csproj
index f7f8622..8fd5410 100644
--- a/Anthropic.SDK.Tests/Anthropic.SDK.Tests.csproj
+++ b/Anthropic.SDK.Tests/Anthropic.SDK.Tests.csproj
@@ -35,13 +35,13 @@
   <ItemGroup>
     <PackageReference Include="Google.Cloud.AIPlatform.V1" Version="3.24.0" />
     <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="8.0.0" />
-    <PackageReference Include="Microsoft.Extensions.AI" Version="9.3.0-preview.1.25161.3" />
+    <PackageReference Include="Microsoft.Extensions.AI" Version="9.4.0-preview.1.25207.5" />
     <PackageReference Include="Microsoft.Extensions.Configuration" Version="8.0.0" />
     <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="8.0.0" />
     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="8.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.13.0" />
-    <PackageReference Include="Microsoft.SemanticKernel" Version="1.42.0" />
-    <PackageReference Include="Microsoft.SemanticKernel.Abstractions" Version="1.42.0" />
+    <PackageReference Include="Microsoft.SemanticKernel" Version="1.47.0" />
+    <PackageReference Include="Microsoft.SemanticKernel.Abstractions" Version="1.47.0" />
     <PackageReference Include="MSTest.TestAdapter" Version="3.8.2" />
     <PackageReference Include="MSTest.TestFramework" Version="3.8.2" />
     <PackageReference Include="coverlet.collector" Version="3.1.2" />
diff --git a/Anthropic.SDK.Tests/Messages.ChatClient.cs b/Anthropic.SDK.Tests/Messages.ChatClient.cs
index fa3c615..5ad6d0a 100644
--- a/Anthropic.SDK.Tests/Messages.ChatClient.cs
+++ b/Anthropic.SDK.Tests/Messages.ChatClient.cs
@@ -97,7 +97,7 @@ public async Task TestThinkingStreamingConversation()
 
             messages.AddMessages(updates);
 
-            Assert.IsTrue(messages.Last().Contents.OfType<Extensions.MEAI.ThinkingContent>().Any());
+            Assert.IsTrue(messages.Last().Contents.OfType<Microsoft.Extensions.AI.TextReasoningContent>().Any());
             
             messages.Add(new ChatMessage(ChatRole.User, "and how many letters total?"));
 
diff --git a/Anthropic.SDK.Tests/VertexAI.ChatClient.cs b/Anthropic.SDK.Tests/VertexAI.ChatClient.cs
index 80a8565..08ae9fb 100644
--- a/Anthropic.SDK.Tests/VertexAI.ChatClient.cs
+++ b/Anthropic.SDK.Tests/VertexAI.ChatClient.cs
@@ -168,7 +168,7 @@ public async Task TestThinkingStreamingConversation()
             
             messages.AddMessages(updates);
             
-            Assert.IsTrue(messages.Last().Contents.OfType<Extensions.MEAI.ThinkingContent>().Any());
+            Assert.IsTrue(messages.Last().Contents.OfType<Microsoft.Extensions.AI.TextReasoningContent>().Any());
             
             messages.Add(new ChatMessage(ChatRole.User, "and how many letters total?"));
 
diff --git a/Anthropic.SDK/Anthropic.SDK.csproj b/Anthropic.SDK/Anthropic.SDK.csproj
index 3413852..e9d4e2d 100644
--- a/Anthropic.SDK/Anthropic.SDK.csproj
+++ b/Anthropic.SDK/Anthropic.SDK.csproj
@@ -34,7 +34,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.AI.Abstractions" Version="9.3.0-preview.1.25161.3" />
+    <PackageReference Include="Microsoft.Extensions.AI.Abstractions" Version="9.4.0-preview.1.25207.5" />
     <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="8.0.0" />
   </ItemGroup>
 
diff --git a/Anthropic.SDK/Extensions/MEAI.cs b/Anthropic.SDK/Extensions/MEAI.cs
index e6b13bd..1b7dec4 100644
--- a/Anthropic.SDK/Extensions/MEAI.cs
+++ b/Anthropic.SDK/Extensions/MEAI.cs
@@ -4,19 +4,6 @@
 
 namespace Anthropic.SDK.Extensions.MEAI
 {
-    public sealed class ThinkingContent : Microsoft.Extensions.AI.AIContent
-    {
-        public ThinkingContent(string thinking, string signature)
-        {
-            Thinking = thinking;
-            Signature = signature;
-        }
-        public string Thinking { get; set; }
-
-        public string Signature { get; set; }
-        public override string ToString() => Thinking;
-    }
-
     public sealed class RedactedThinkingContent : Microsoft.Extensions.AI.AIContent
     {
         public RedactedThinkingContent(string data)
diff --git a/Anthropic.SDK/Messaging/ChatClientHelper.cs b/Anthropic.SDK/Messaging/ChatClientHelper.cs
index 71551ce..dea092b 100644
--- a/Anthropic.SDK/Messaging/ChatClientHelper.cs
+++ b/Anthropic.SDK/Messaging/ChatClientHelper.cs
@@ -111,8 +111,12 @@ public static MessageParameters CreateMessageParameters(IEnumerable<ChatMessage>
                     {
                         switch (content)
                         {
-                            case Anthropic.SDK.Extensions.MEAI.ThinkingContent thinkingContent:
-                                m.Content.Add(new Messaging.ThinkingContent() { Thinking = thinkingContent.Thinking, Signature = thinkingContent.Signature });
+                            case Microsoft.Extensions.AI.TextReasoningContent textReasoningContent:
+                                m.Content.Add(new Messaging.ThinkingContent()
+                                {
+                                    Thinking = textReasoningContent.Text,
+                                    Signature = textReasoningContent.AdditionalProperties[nameof(ThinkingContent.Signature)]?.ToString()
+                                });
                                 break;
 
                             case Anthropic.SDK.Extensions.MEAI.RedactedThinkingContent redactedThinkingContent:
@@ -182,7 +186,13 @@ public static List<AIContent> ProcessResponseContent(MessageResponse response)
                 switch (content)
                 {
                     case Messaging.ThinkingContent thinkingContent:
-                        contents.Add(new Anthropic.SDK.Extensions.MEAI.ThinkingContent(thinkingContent.Thinking, thinkingContent.Signature));
+                        contents.Add(new Microsoft.Extensions.AI.TextReasoningContent(thinkingContent.Thinking)
+                        {
+                            AdditionalProperties = new AdditionalPropertiesDictionary
+                            {
+                                [nameof(ThinkingContent.Signature)] = thinkingContent.Signature
+                            }
+                        });
                         break;
 
                     case Messaging.RedactedThinkingContent redactedThinkingContent:
diff --git a/Anthropic.SDK/Messaging/MessagesEndpoint.ChatClient.cs b/Anthropic.SDK/Messaging/MessagesEndpoint.ChatClient.cs
index 601c6ce..376b01d 100644
--- a/Anthropic.SDK/Messaging/MessagesEndpoint.ChatClient.cs
+++ b/Anthropic.SDK/Messaging/MessagesEndpoint.ChatClient.cs
@@ -126,7 +126,13 @@ async IAsyncEnumerable<ChatResponseUpdate> IChatClient.GetStreamingResponseAsync
 
                 if (!string.IsNullOrEmpty(response.Delta.Signature))
                 {
-                    update.Contents.Add(new Anthropic.SDK.Extensions.MEAI.ThinkingContent(thinking, response.Delta.Signature));
+                    update.Contents.Add(new TextReasoningContent(thinking)
+                    {
+                        AdditionalProperties = new AdditionalPropertiesDictionary
+                        {
+                            [nameof(ThinkingContent.Signature)] = response.Delta.Signature
+                        }
+                    });
                 }
 
 
diff --git a/Anthropic.SDK/Messaging/VertexAIMessagesEndpoint.ChatClient.cs b/Anthropic.SDK/Messaging/VertexAIMessagesEndpoint.ChatClient.cs
index 81956b2..d411775 100644
--- a/Anthropic.SDK/Messaging/VertexAIMessagesEndpoint.ChatClient.cs
+++ b/Anthropic.SDK/Messaging/VertexAIMessagesEndpoint.ChatClient.cs
@@ -78,7 +78,13 @@ async IAsyncEnumerable<ChatResponseUpdate> IChatClient.GetStreamingResponseAsync
 
                 if (!string.IsNullOrEmpty(response.Delta.Signature))
                 {
-                    update.Contents.Add(new Anthropic.SDK.Extensions.MEAI.ThinkingContent(thinking, response.Delta.Signature));
+                    update.Contents.Add(new Microsoft.Extensions.AI.TextReasoningContent(thinking)
+                    {
+                        AdditionalProperties = new AdditionalPropertiesDictionary
+                        {
+                            [nameof(ThinkingContent.Signature)] = response.Delta.Signature
+                        }
+                    });
                 }