diff --git a/dotnet/tests/Microsoft.Agents.AI.Declarative.UnitTests/AggregatorPromptAgentFactoryTests.cs b/dotnet/tests/Microsoft.Agents.AI.Declarative.UnitTests/AggregatorPromptAgentFactoryTests.cs
index 09ee72504a..7c763243bc 100644
--- a/dotnet/tests/Microsoft.Agents.AI.Declarative.UnitTests/AggregatorPromptAgentFactoryTests.cs
+++ b/dotnet/tests/Microsoft.Agents.AI.Declarative.UnitTests/AggregatorPromptAgentFactoryTests.cs
@@ -66,12 +66,12 @@ public sealed class AggregatorPromptAgentFactoryTests
 
     private sealed class TestAgent : AIAgent
     {
-        public override AgentThread DeserializeThread(JsonElement serializedThread, JsonSerializerOptions? jsonSerializerOptions = null)
+        public override AgentThread DeserializeThread(JsonElement serializedThread, JsonSerializerOptions? jsonSerializerOptions = null, IAgentFeatureCollection? featureCollection = null)
         {
             throw new NotImplementedException();
         }
 
-        public override AgentThread GetNewThread()
+        public override AgentThread GetNewThread(IAgentFeatureCollection? featureCollection = null)
         {
             throw new NotImplementedException();
         }
diff --git a/dotnet/tests/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore.IntegrationTests/ForwardedPropertiesTests.cs b/dotnet/tests/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore.IntegrationTests/ForwardedPropertiesTests.cs
index 1777ff456a..ae40948a5b 100644
--- a/dotnet/tests/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore.IntegrationTests/ForwardedPropertiesTests.cs
+++ b/dotnet/tests/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore.IntegrationTests/ForwardedPropertiesTests.cs
@@ -334,9 +334,9 @@ internal sealed class FakeForwardedPropsAgent : AIAgent
         await Task.CompletedTask;
     }
 
-    public override AgentThread GetNewThread() => new FakeInMemoryAgentThread();
+    public override AgentThread GetNewThread(IAgentFeatureCollection? featureCollection = null) => new FakeInMemoryAgentThread();
 
-    public override AgentThread DeserializeThread(JsonElement serializedThread, JsonSerializerOptions? jsonSerializerOptions = null)
+    public override AgentThread DeserializeThread(JsonElement serializedThread, JsonSerializerOptions? jsonSerializerOptions = null, IAgentFeatureCollection? featureCollection = null)
     {
         return new FakeInMemoryAgentThread(serializedThread, jsonSerializerOptions);
     }
diff --git a/dotnet/tests/Microsoft.Agents.AI.UnitTests/ChatClient/ChatClientAgent_DeserializeThreadTests.cs b/dotnet/tests/Microsoft.Agents.AI.UnitTests/ChatClient/ChatClientAgent_DeserializeThreadTests.cs
index dc1407154e..8edbc2cadc 100644
--- a/dotnet/tests/Microsoft.Agents.AI.UnitTests/ChatClient/ChatClientAgent_DeserializeThreadTests.cs
+++ b/dotnet/tests/Microsoft.Agents.AI.UnitTests/ChatClient/ChatClientAgent_DeserializeThreadTests.cs
@@ -85,7 +85,7 @@ public class ChatClientAgent_DeserializeThreadTests
         var mockMessageStore = new Mock<ChatMessageStore>();
         var agent = new ChatClientAgent(mockChatClient.Object, new ChatClientAgentOptions
         {
-            Instructions = "Test instructions",
+            ChatOptions = new ChatOptions { Instructions = "Test instructions" },
             ChatMessageStoreFactory = _ =>
             {
                 Assert.Fail("ChatMessageStoreFactory should not have been called.");
@@ -117,7 +117,7 @@ public class ChatClientAgent_DeserializeThreadTests
         var mockContextProvider = new Mock<AIContextProvider>();
         var agent = new ChatClientAgent(mockChatClient.Object, new ChatClientAgentOptions
         {
-            Instructions = "Test instructions",
+            ChatOptions = new ChatOptions { Instructions = "Test instructions" },
             AIContextProviderFactory = _ =>
             {
                 Assert.Fail("AIContextProviderFactory should not have been called.");