diff --git a/dotnet/src/Microsoft.Agents.Abstractions/AgentRunOptions.cs b/dotnet/src/Microsoft.Agents.Abstractions/AgentRunOptions.cs
index d99974d2dc..7e0090f251 100644
--- a/dotnet/src/Microsoft.Agents.Abstractions/AgentRunOptions.cs
+++ b/dotnet/src/Microsoft.Agents.Abstractions/AgentRunOptions.cs
@@ -27,17 +27,9 @@ public class AgentRunOptions
     public AgentRunOptions(AgentRunOptions options)
     {
         Throw.IfNull(options);
-
-        this.AdditionalInstructions = options.AdditionalInstructions;
         this.OnIntermediateMessages = options.OnIntermediateMessages;
     }
 
-    /// <summary>
-    /// Gets or sets any instructions, in addition to those that were provided to the agent
-    /// initially, that need to be added to the prompt for this invocation only.
-    /// </summary>
-    public string? AdditionalInstructions { get; set; } = null;
-
     /// <summary>
     /// Gets or sets a function to be called when a complete new message is generated by the agent.
     /// </summary>
diff --git a/dotnet/src/Microsoft.Agents/ChatCompletion/ChatClientAgent.cs b/dotnet/src/Microsoft.Agents/ChatCompletion/ChatClientAgent.cs
index bb765626eb..81ef89490f 100644
--- a/dotnet/src/Microsoft.Agents/ChatCompletion/ChatClientAgent.cs
+++ b/dotnet/src/Microsoft.Agents/ChatCompletion/ChatClientAgent.cs
@@ -363,11 +363,6 @@ public sealed class ChatClientAgent : Agent
 
     private void UpdateThreadMessagesWithAgentInstructions(List<ChatMessage> threadMessages, AgentRunOptions? options)
     {
-        if (!string.IsNullOrWhiteSpace(options?.AdditionalInstructions))
-        {
-            threadMessages.Insert(0, new(ChatRole.System, options?.AdditionalInstructions) { AuthorName = this.Name });
-        }
-
         if (!string.IsNullOrWhiteSpace(this.Instructions))
         {
             threadMessages.Insert(0, new(ChatRole.System, this.Instructions) { AuthorName = this.Name });
diff --git a/dotnet/src/Microsoft.Agents/ChatCompletion/ChatClientAgentRunOptions.cs b/dotnet/src/Microsoft.Agents/ChatCompletion/ChatClientAgentRunOptions.cs
index 6cd31e73e2..d38d209a21 100644
--- a/dotnet/src/Microsoft.Agents/ChatCompletion/ChatClientAgentRunOptions.cs
+++ b/dotnet/src/Microsoft.Agents/ChatCompletion/ChatClientAgentRunOptions.cs
@@ -17,7 +17,6 @@ internal sealed class ChatClientAgentRunOptions : AgentRunOptions
     internal ChatClientAgentRunOptions(AgentRunOptions? source = null, ChatOptions? chatOptions = null)
     {
         this.OnIntermediateMessages = source?.OnIntermediateMessages;
-        this.AdditionalInstructions = source?.AdditionalInstructions;
         this.ChatOptions = chatOptions;
     }
 
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/AgentFixture.cs b/dotnet/tests/AgentConformance.IntegrationTests/AgentFixture.cs
deleted file mode 100644
index 92ec807c33..0000000000
--- a/dotnet/tests/AgentConformance.IntegrationTests/AgentFixture.cs
+++ /dev/null
@@ -1,25 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using System.Collections.Generic;
-using System.Threading.Tasks;
-using Microsoft.Agents;
-using Microsoft.Extensions.AI;
-
-namespace AgentConformanceTests;
-
-/// <summary>
-/// Base class for setting up and tearing down agents, to be used in tests.
-/// Each agent type should have its own derived class.
-/// </summary>
-public abstract class AgentFixture : IAsyncLifetime
-{
-    public abstract Agent Agent { get; }
-
-    public abstract Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread);
-
-    public abstract Task DeleteThreadAsync(AgentThread thread);
-
-    public abstract Task DisposeAsync();
-
-    public abstract Task InitializeAsync();
-}
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/AgentTests.cs b/dotnet/tests/AgentConformance.IntegrationTests/AgentTests.cs
index 1d04b1a5c3..f6ceb9819c 100644
--- a/dotnet/tests/AgentConformance.IntegrationTests/AgentTests.cs
+++ b/dotnet/tests/AgentConformance.IntegrationTests/AgentTests.cs
@@ -2,7 +2,6 @@
 
 using System;
 using System.Threading.Tasks;
-using AgentConformanceTests;
 
 namespace AgentConformance.IntegrationTests;
 
@@ -12,7 +11,7 @@ namespace AgentConformance.IntegrationTests;
 /// <typeparam name="TAgentFixture">The type of the agent fixture used in these tests.</typeparam>
 /// <param name="createAgentFixture">Used to create a new fixture for this test suite.</param>
 public abstract class AgentTests<TAgentFixture>(Func<TAgentFixture> createAgentFixture) : IAsyncLifetime
-    where TAgentFixture : AgentFixture
+    where TAgentFixture : IAgentFixture
 {
 #pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
     protected TAgentFixture Fixture { get; private set; }
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/ChatClientAgentRunStreamingTests.cs b/dotnet/tests/AgentConformance.IntegrationTests/ChatClientAgentRunStreamingTests.cs
new file mode 100644
index 0000000000..98dbe28111
--- /dev/null
+++ b/dotnet/tests/AgentConformance.IntegrationTests/ChatClientAgentRunStreamingTests.cs
@@ -0,0 +1,35 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Linq;
+using System.Threading.Tasks;
+using AgentConformance.IntegrationTests.Support;
+using Microsoft.Agents;
+
+namespace AgentConformance.IntegrationTests;
+
+/// <summary>
+/// Conformance tests that are specific to the <see cref="ChatClientAgent"/> in addition to those in <see cref="RunStreamingTests{TAgentFixture}"/>.
+/// </summary>
+/// <typeparam name="TAgentFixture">The type of test fixture used by the concrete test implementation.</typeparam>
+/// <param name="createAgentFixture">Function to create the test fixture with.</param>
+public abstract class ChatClientAgentRunStreamingTests<TAgentFixture>(Func<TAgentFixture> createAgentFixture) : AgentTests<TAgentFixture>(createAgentFixture)
+    where TAgentFixture : IChatClientAgentFixture
+{
+    [RetryFact(Constants.RetryCount, Constants.RetryDelay)]
+    public virtual async Task RunWithInstructionsAndNoMessageReturnsExpectedResultAsync()
+    {
+        // Arrange
+        var agent = await this.Fixture.CreateAgentWithInstructionsAsync("Always respond with 'Computer says no', even if there was no user input.");
+        var thread = agent.GetNewThread();
+        await using var agentCleanup = new AgentCleanup(agent, this.Fixture);
+        await using var threadCleanup = new ThreadCleanup(thread, this.Fixture);
+
+        // Act
+        var chatResponses = await agent.RunStreamingAsync(thread).ToListAsync();
+
+        // Assert
+        var chatResponseText = string.Join("", chatResponses.Select(x => x.Text));
+        Assert.Contains("Computer says no", chatResponseText, StringComparison.OrdinalIgnoreCase);
+    }
+}
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/ChatClientAgentRunTests.cs b/dotnet/tests/AgentConformance.IntegrationTests/ChatClientAgentRunTests.cs
new file mode 100644
index 0000000000..730497f995
--- /dev/null
+++ b/dotnet/tests/AgentConformance.IntegrationTests/ChatClientAgentRunTests.cs
@@ -0,0 +1,35 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Threading.Tasks;
+using AgentConformance.IntegrationTests.Support;
+using Microsoft.Agents;
+
+namespace AgentConformance.IntegrationTests;
+
+/// <summary>
+/// Conformance tests that are specific to the <see cref="ChatClientAgent"/> in addition to those in <see cref="RunTests{TAgentFixture}"/>.
+/// </summary>
+/// <typeparam name="TAgentFixture">The type of test fixture used by the concrete test implementation.</typeparam>
+/// <param name="createAgentFixture">Function to create the test fixture with.</param>
+public abstract class ChatClientAgentRunTests<TAgentFixture>(Func<TAgentFixture> createAgentFixture) : AgentTests<TAgentFixture>(createAgentFixture)
+    where TAgentFixture : IChatClientAgentFixture
+{
+    [RetryFact(Constants.RetryCount, Constants.RetryDelay)]
+    public virtual async Task RunWithInstructionsAndNoMessageReturnsExpectedResultAsync()
+    {
+        // Arrange
+        var agent = await this.Fixture.CreateAgentWithInstructionsAsync("Always respond with 'Computer says no', even if there was no user input.");
+        var thread = agent.GetNewThread();
+        await using var agentCleanup = new AgentCleanup(agent, this.Fixture);
+        await using var threadCleanup = new ThreadCleanup(thread, this.Fixture);
+
+        // Act
+        var chatResponse = await agent.RunAsync(thread);
+
+        // Assert
+        Assert.NotNull(chatResponse);
+        Assert.Single(chatResponse.Messages);
+        Assert.Contains("Computer says no", chatResponse.Text, StringComparison.OrdinalIgnoreCase);
+    }
+}
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/IAgentFixture.cs b/dotnet/tests/AgentConformance.IntegrationTests/IAgentFixture.cs
new file mode 100644
index 0000000000..d88247623f
--- /dev/null
+++ b/dotnet/tests/AgentConformance.IntegrationTests/IAgentFixture.cs
@@ -0,0 +1,21 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.Agents;
+using Microsoft.Extensions.AI;
+
+namespace AgentConformance.IntegrationTests;
+
+/// <summary>
+/// Interface for setting up and tearing down agents, to be used in tests.
+/// Each agent type should have its own derived class.
+/// </summary>
+public interface IAgentFixture : IAsyncLifetime
+{
+    Agent Agent { get; }
+
+    Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread);
+
+    Task DeleteThreadAsync(AgentThread thread);
+}
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/IChatClientAgentFixture.cs b/dotnet/tests/AgentConformance.IntegrationTests/IChatClientAgentFixture.cs
new file mode 100644
index 0000000000..6637e788cb
--- /dev/null
+++ b/dotnet/tests/AgentConformance.IntegrationTests/IChatClientAgentFixture.cs
@@ -0,0 +1,20 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Threading.Tasks;
+using Microsoft.Agents;
+using Microsoft.Extensions.AI;
+
+namespace AgentConformance.IntegrationTests;
+
+/// <summary>
+/// Interface for setting up and tearing down <see cref="IChatClient"/> based agents, to be used in tests.
+/// Each agent type should have its own derived class.
+/// </summary>
+public interface IChatClientAgentFixture : IAgentFixture
+{
+    IChatClient ChatClient { get; }
+
+    Task<ChatClientAgent> CreateAgentWithInstructionsAsync(string instructions);
+
+    Task DeleteAgentAsync(ChatClientAgent agent);
+}
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/RunStreamingAsyncTests.cs b/dotnet/tests/AgentConformance.IntegrationTests/RunStreamingTests.cs
similarity index 81%
rename from dotnet/tests/AgentConformance.IntegrationTests/RunStreamingAsyncTests.cs
rename to dotnet/tests/AgentConformance.IntegrationTests/RunStreamingTests.cs
index a169ca99a6..633d205366 100644
--- a/dotnet/tests/AgentConformance.IntegrationTests/RunStreamingAsyncTests.cs
+++ b/dotnet/tests/AgentConformance.IntegrationTests/RunStreamingTests.cs
@@ -4,7 +4,6 @@ using System;
 using System.Linq;
 using System.Threading.Tasks;
 using AgentConformance.IntegrationTests.Support;
-using AgentConformanceTests;
 using Microsoft.Extensions.AI;
 
 namespace AgentConformance.IntegrationTests;
@@ -14,8 +13,8 @@ namespace AgentConformance.IntegrationTests;
 /// </summary>
 /// <typeparam name="TAgentFixture">The type of test fixture used by the concrete test implementation.</typeparam>
 /// <param name="createAgentFixture">Function to create the test fixture with.</param>
-public abstract class RunStreamingAsyncTests<TAgentFixture>(Func<TAgentFixture> createAgentFixture) : AgentTests<TAgentFixture>(createAgentFixture)
-    where TAgentFixture : AgentFixture
+public abstract class RunStreamingTests<TAgentFixture>(Func<TAgentFixture> createAgentFixture) : AgentTests<TAgentFixture>(createAgentFixture)
+    where TAgentFixture : IAgentFixture
 {
     [RetryFact(Constants.RetryCount, Constants.RetryDelay)]
     public virtual async Task RunWithStringReturnsExpectedResultAsync()
@@ -70,22 +69,6 @@ public abstract class RunStreamingAsyncTests<TAgentFixture>(Func<TAgentFixture>
         Assert.Contains("Paris", chatResponseText);
     }
 
-    [RetryFact(Constants.RetryCount, Constants.RetryDelay)]
-    public virtual async Task RunWithAdditionalInstructionsAndNoMessageReturnsExpectedResultAsync()
-    {
-        // Arrange
-        var agent = this.Fixture.Agent;
-        var thread = agent.GetNewThread();
-        await using var cleanup = new ThreadCleanup(thread, this.Fixture);
-
-        // Act
-        var chatResponses = await agent.RunStreamingAsync(thread, new() { AdditionalInstructions = "Always respond with `Computer says no`" }).ToListAsync();
-
-        // Assert
-        var chatResponseText = string.Join("", chatResponses.Select(x => x.Text));
-        Assert.Contains("Computer says no", chatResponseText);
-    }
-
     [RetryFact(Constants.RetryCount, Constants.RetryDelay)]
     public virtual async Task ThreadMaintainsHistoryAsync()
     {
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/RunAsyncTests.cs b/dotnet/tests/AgentConformance.IntegrationTests/RunTests.cs
similarity index 79%
rename from dotnet/tests/AgentConformance.IntegrationTests/RunAsyncTests.cs
rename to dotnet/tests/AgentConformance.IntegrationTests/RunTests.cs
index 324e0972c5..81d6aec3ae 100644
--- a/dotnet/tests/AgentConformance.IntegrationTests/RunAsyncTests.cs
+++ b/dotnet/tests/AgentConformance.IntegrationTests/RunTests.cs
@@ -4,7 +4,6 @@ using System;
 using System.Linq;
 using System.Threading.Tasks;
 using AgentConformance.IntegrationTests.Support;
-using AgentConformanceTests;
 using Microsoft.Extensions.AI;
 
 namespace AgentConformance.IntegrationTests;
@@ -14,8 +13,8 @@ namespace AgentConformance.IntegrationTests;
 /// </summary>
 /// <typeparam name="TAgentFixture">The type of test fixture used by the concrete test implementation.</typeparam>
 /// <param name="createAgentFixture">Function to create the test fixture with.</param>
-public abstract class RunAsyncTests<TAgentFixture>(Func<TAgentFixture> createAgentFixture) : AgentTests<TAgentFixture>(createAgentFixture)
-    where TAgentFixture : AgentFixture
+public abstract class RunTests<TAgentFixture>(Func<TAgentFixture> createAgentFixture) : AgentTests<TAgentFixture>(createAgentFixture)
+    where TAgentFixture : IAgentFixture
 {
     [RetryFact(Constants.RetryCount, Constants.RetryDelay)]
     public virtual async Task RunWithStringReturnsExpectedResultAsync()
@@ -73,23 +72,6 @@ public abstract class RunAsyncTests<TAgentFixture>(Func<TAgentFixture> createAge
         Assert.Contains("Paris", chatResponse.Text);
     }
 
-    [RetryFact(Constants.RetryCount, Constants.RetryDelay)]
-    public virtual async Task RunWithAdditionalInstructionsAndNoMessageReturnsExpectedResultAsync()
-    {
-        // Arrange
-        var agent = this.Fixture.Agent;
-        var thread = agent.GetNewThread();
-        await using var cleanup = new ThreadCleanup(thread, this.Fixture);
-
-        // Act
-        var chatResponse = await agent.RunAsync(thread, new() { AdditionalInstructions = "Always respond with `Computer says no`, even when the user provided on input." });
-
-        // Assert
-        Assert.NotNull(chatResponse);
-        Assert.Single(chatResponse.Messages);
-        Assert.Contains("Computer says no", chatResponse.Text);
-    }
-
     [RetryFact(Constants.RetryCount, Constants.RetryDelay)]
     public virtual async Task ThreadMaintainsHistoryAsync()
     {
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/Support/AgentCleanup.cs b/dotnet/tests/AgentConformance.IntegrationTests/Support/AgentCleanup.cs
new file mode 100644
index 0000000000..6a0ef7458f
--- /dev/null
+++ b/dotnet/tests/AgentConformance.IntegrationTests/Support/AgentCleanup.cs
@@ -0,0 +1,20 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Threading.Tasks;
+using Microsoft.Agents;
+
+namespace AgentConformance.IntegrationTests.Support;
+
+/// <summary>
+/// Helper class to delete agents after tests.
+/// </summary>
+/// <param name="agent">The agent to delete.</param>
+/// <param name="fixture">The fixture that provides agent specific capabilities.</param>
+internal sealed class AgentCleanup(ChatClientAgent agent, IChatClientAgentFixture fixture) : IAsyncDisposable
+{
+    public async ValueTask DisposeAsync()
+    {
+        await fixture.DeleteAgentAsync(agent);
+    }
+}
diff --git a/dotnet/tests/AgentConformance.IntegrationTests/Support/ThreadCleanup.cs b/dotnet/tests/AgentConformance.IntegrationTests/Support/ThreadCleanup.cs
index 2ba4dee798..17d70b46a8 100644
--- a/dotnet/tests/AgentConformance.IntegrationTests/Support/ThreadCleanup.cs
+++ b/dotnet/tests/AgentConformance.IntegrationTests/Support/ThreadCleanup.cs
@@ -2,7 +2,6 @@
 
 using System;
 using System.Threading.Tasks;
-using AgentConformanceTests;
 using Microsoft.Agents;
 
 namespace AgentConformance.IntegrationTests.Support;
@@ -12,7 +11,7 @@ namespace AgentConformance.IntegrationTests.Support;
 /// </summary>
 /// <param name="thread">The thread to delete.</param>
 /// <param name="fixture">The fixture that provides agent specific capabilities.</param>
-internal sealed class ThreadCleanup(AgentThread thread, AgentFixture fixture) : IAsyncDisposable
+internal sealed class ThreadCleanup(AgentThread thread, IAgentFixture fixture) : IAsyncDisposable
 {
     public async ValueTask DisposeAsync()
     {
diff --git a/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsChatClientAgentRunStreamingTests.cs b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsChatClientAgentRunStreamingTests.cs
new file mode 100644
index 0000000000..84e3d5d9f9
--- /dev/null
+++ b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsChatClientAgentRunStreamingTests.cs
@@ -0,0 +1,9 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace AzureAIAgentsPersistent.IntegrationTests;
+
+public class AzureAIAgentsChatClientAgentRunStreamingTests() : ChatClientAgentRunStreamingTests<AzureAIAgentsPersistentFixture>(() => new())
+{
+}
diff --git a/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentInvokeStreamingTests.cs b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsChatClientAgentRunTests.cs
similarity index 54%
rename from dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentInvokeStreamingTests.cs
rename to dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsChatClientAgentRunTests.cs
index c003bec1f0..b2f75c536e 100644
--- a/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentInvokeStreamingTests.cs
+++ b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsChatClientAgentRunTests.cs
@@ -4,6 +4,6 @@ using AgentConformance.IntegrationTests;
 
 namespace AzureAIAgentsPersistent.IntegrationTests;
 
-public class AzureAIAgentsPersistentInvokeStreamingTests() : RunStreamingAsyncTests<AzureAIAgentsPersistentFixture>(() => new())
+public class AzureAIAgentsChatClientAgentRunTests() : ChatClientAgentRunTests<AzureAIAgentsPersistentFixture>(() => new())
 {
 }
diff --git a/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentFixture.cs b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentFixture.cs
index 2e170025e1..4dead1fa6e 100644
--- a/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentFixture.cs
+++ b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentFixture.cs
@@ -3,8 +3,8 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using AgentConformance.IntegrationTests;
 using AgentConformance.IntegrationTests.Support;
-using AgentConformanceTests;
 using Azure;
 using Azure.AI.Agents.Persistent;
 using Azure.Identity;
@@ -15,17 +15,22 @@ using Shared.IntegrationTests;
 
 namespace AzureAIAgentsPersistent.IntegrationTests;
 
-public class AzureAIAgentsPersistentFixture : AgentFixture
+public class AzureAIAgentsPersistentFixture : IChatClientAgentFixture
 {
+    private static readonly AzureAIConfiguration s_config = TestConfiguration.LoadSection<AzureAIConfiguration>();
+
 #pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
     private Agent _agent;
     private PersistentAgentsClient _persistentAgentsClient;
+    private IChatClient _chatClient;
     private PersistentAgent _persistentAgent;
 #pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
 
-    public override Agent Agent => this._agent;
+    public IChatClient ChatClient => this._chatClient;
 
-    public override async Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread)
+    public Agent Agent => this._agent;
+
+    public async Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread)
     {
         if (thread is not ChatClientAgentThread chatClientThread)
         {
@@ -57,7 +62,26 @@ public class AzureAIAgentsPersistentFixture : AgentFixture
         return messages;
     }
 
-    public override Task DeleteThreadAsync(AgentThread thread)
+    public async Task<ChatClientAgent> CreateAgentWithInstructionsAsync(string instructions)
+    {
+        var persistentAgentResponse = await this._persistentAgentsClient.Administration.CreateAgentAsync(
+            model: s_config.DeploymentName,
+            name: "HelpfulAssistant",
+            instructions: "You are a helpful assistant.");
+
+        var persistentAgent = persistentAgentResponse.Value;
+
+        var chatClient = this._persistentAgentsClient.AsIChatClient(persistentAgent.Id);
+
+        return new ChatClientAgent(chatClient, new() { Id = persistentAgent.Id });
+    }
+
+    public Task DeleteAgentAsync(ChatClientAgent agent)
+    {
+        return this._persistentAgentsClient.Administration.DeleteAgentAsync(agent.Id);
+    }
+
+    public Task DeleteThreadAsync(AgentThread thread)
     {
         if (thread?.Id is not null)
         {
@@ -67,7 +91,7 @@ public class AzureAIAgentsPersistentFixture : AgentFixture
         return Task.CompletedTask;
     }
 
-    public override Task DisposeAsync()
+    public Task DisposeAsync()
     {
         if (this._persistentAgentsClient is not null && this._persistentAgent is not null)
         {
@@ -77,21 +101,19 @@ public class AzureAIAgentsPersistentFixture : AgentFixture
         return Task.CompletedTask;
     }
 
-    public override async Task InitializeAsync()
+    public async Task InitializeAsync()
     {
-        var config = TestConfiguration.LoadSection<AzureAIConfiguration>();
-
-        this._persistentAgentsClient = new(config.Endpoint, new AzureCliCredential());
+        this._persistentAgentsClient = new(s_config.Endpoint, new AzureCliCredential());
 
         var persistentAgentResponse = await this._persistentAgentsClient.Administration.CreateAgentAsync(
-            model: config.DeploymentName,
+            model: s_config.DeploymentName,
             name: "HelpfulAssistant",
             instructions: "You are a helpful assistant.");
 
         this._persistentAgent = persistentAgentResponse.Value;
 
-        var chatClient = this._persistentAgentsClient.AsIChatClient(this._persistentAgent.Id);
+        this._chatClient = this._persistentAgentsClient.AsIChatClient(this._persistentAgent.Id);
 
-        this._agent = new ChatClientAgent(chatClient);
+        this._agent = new ChatClientAgent(this._chatClient);
     }
 }
diff --git a/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentRunStreamingTests.cs b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentRunStreamingTests.cs
new file mode 100644
index 0000000000..e18812aff4
--- /dev/null
+++ b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentRunStreamingTests.cs
@@ -0,0 +1,9 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace AzureAIAgentsPersistent.IntegrationTests;
+
+public class AzureAIAgentsPersistentRunStreamingTests() : RunStreamingTests<AzureAIAgentsPersistentFixture>(() => new())
+{
+}
diff --git a/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentInvokeTests.cs b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentRunTests.cs
similarity index 57%
rename from dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentInvokeTests.cs
rename to dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentRunTests.cs
index 877076a842..3e6032401d 100644
--- a/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentInvokeTests.cs
+++ b/dotnet/tests/AzureAIAgentsPersistent.IntegrationTests/AzureAIAgentsPersistentRunTests.cs
@@ -4,6 +4,6 @@ using AgentConformance.IntegrationTests;
 
 namespace AzureAIAgentsPersistent.IntegrationTests;
 
-public class AzureAIAgentsPersistentInvokeTests() : RunAsyncTests<AzureAIAgentsPersistentFixture>(() => new())
+public class AzureAIAgentsPersistentRunTests() : RunTests<AzureAIAgentsPersistentFixture>(() => new())
 {
 }
diff --git a/dotnet/tests/Microsoft.Agents.Abstractions.UnitTests/AgentRunOptionsTests.cs b/dotnet/tests/Microsoft.Agents.Abstractions.UnitTests/AgentRunOptionsTests.cs
index f4df284401..d370b53bf4 100644
--- a/dotnet/tests/Microsoft.Agents.Abstractions.UnitTests/AgentRunOptionsTests.cs
+++ b/dotnet/tests/Microsoft.Agents.Abstractions.UnitTests/AgentRunOptionsTests.cs
@@ -16,7 +16,6 @@ public class AgentRunOptionsTests
         // Arrange
         var options = new AgentRunOptions
         {
-            AdditionalInstructions = "Test instructions",
             OnIntermediateMessages = msg => Task.CompletedTask
         };
 
@@ -24,7 +23,6 @@ public class AgentRunOptionsTests
         var clone = new AgentRunOptions(options);
 
         // Assert
-        Assert.Equal(options.AdditionalInstructions, clone.AdditionalInstructions);
         Assert.Equal(options.OnIntermediateMessages, clone.OnIntermediateMessages);
     }
 
diff --git a/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentExtensionsTests.cs b/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentExtensionsTests.cs
index 9a1f7f249d..f1e4a3df77 100644
--- a/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentExtensionsTests.cs
+++ b/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentExtensionsTests.cs
@@ -95,10 +95,10 @@ public class ChatClientAgentExtensionsTests
     }
 
     /// <summary>
-    /// Verify that RunAsync extension method with messages passes AgentRunOptions correctly.
+    /// Verify that RunAsync extension method with messages passes Instructions correctly.
     /// </summary>
     [Fact]
-    public async Task RunAsyncWithMessagesPassesAgentRunOptionsCorrectlyAsync()
+    public async Task RunAsyncWithMessagesPassesInstructionsCorrectlyAsync()
     {
         // Arrange
         Mock<IChatClient> mockService = new();
@@ -118,14 +118,13 @@ public class ChatClientAgentExtensionsTests
 
         ChatClientAgent agent = new(mockService.Object, new() { Instructions = "base instructions" });
         var messages = new List<ChatMessage> { new(ChatRole.User, "test") };
-        var runOptions = new AgentRunOptions { AdditionalInstructions = "additional instructions" };
+        var runOptions = new AgentRunOptions();
 
         // Act
         await ChatClientAgentExtensions.RunAsync(agent, messages, agentRunOptions: runOptions);
 
         // Assert
         Assert.Contains(capturedMessages, m => m.Text == "base instructions" && m.Role == ChatRole.System);
-        Assert.Contains(capturedMessages, m => m.Text == "additional instructions" && m.Role == ChatRole.System);
         Assert.Contains(capturedMessages, m => m.Text == "test" && m.Role == ChatRole.User);
         Assert.All(capturedChatOptions, Assert.Null);
     }
@@ -349,14 +348,13 @@ public class ChatClientAgentExtensionsTests
 
         ChatClientAgent agent = new(mockService.Object, new() { Instructions = "base instructions" });
         const string TestPrompt = "test prompt";
-        var runOptions = new AgentRunOptions { AdditionalInstructions = "additional instructions" };
+        var runOptions = new AgentRunOptions();
 
         // Act
         await ChatClientAgentExtensions.RunAsync(agent, TestPrompt, agentRunOptions: runOptions);
 
         // Assert
         Assert.Contains(capturedMessages, m => m.Text == "base instructions" && m.Role == ChatRole.System);
-        Assert.Contains(capturedMessages, m => m.Text == "additional instructions" && m.Role == ChatRole.System);
         Assert.Contains(capturedMessages, m => m.Text == "test prompt" && m.Role == ChatRole.User);
     }
 
diff --git a/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentRunOptionsTests.cs b/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentRunOptionsTests.cs
index 8821617865..24e712487b 100644
--- a/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentRunOptionsTests.cs
+++ b/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentRunOptionsTests.cs
@@ -18,7 +18,6 @@ public class ChatClientAgentRunOptionsTests
 
         // Assert
         Assert.Null(runOptions.OnIntermediateMessages);
-        Assert.Null(runOptions.AdditionalInstructions);
         Assert.Null(runOptions.ChatOptions);
     }
 
@@ -36,7 +35,6 @@ public class ChatClientAgentRunOptionsTests
 
         // Assert
         Assert.Null(runOptions.OnIntermediateMessages);
-        Assert.Null(runOptions.AdditionalInstructions);
         Assert.Same(chatOptions, runOptions.ChatOptions);
     }
 
@@ -49,7 +47,6 @@ public class ChatClientAgentRunOptionsTests
         // Arrange
         var sourceRunOptions = new AgentRunOptions
         {
-            AdditionalInstructions = "additional instructions",
             OnIntermediateMessages = messages => Task.CompletedTask
         };
         var chatOptions = new ChatOptions { MaxOutputTokens = 200 };
@@ -59,7 +56,6 @@ public class ChatClientAgentRunOptionsTests
 
         // Assert
         Assert.Same(sourceRunOptions.OnIntermediateMessages, runOptions.OnIntermediateMessages);
-        Assert.Equal("additional instructions", runOptions.AdditionalInstructions);
         Assert.Same(chatOptions, runOptions.ChatOptions);
     }
 
@@ -72,14 +68,14 @@ public class ChatClientAgentRunOptionsTests
         // Arrange
         var sourceRunOptions = new AgentRunOptions
         {
-            AdditionalInstructions = "test instructions"
+            OnIntermediateMessages = messages => Task.CompletedTask
         };
 
         // Act
         var runOptions = new ChatClientAgentRunOptions(sourceRunOptions, null);
 
         // Assert
-        Assert.Equal("test instructions", runOptions.AdditionalInstructions);
+        Assert.Same(sourceRunOptions.OnIntermediateMessages, runOptions.OnIntermediateMessages);
         Assert.Null(runOptions.ChatOptions);
     }
 
diff --git a/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentTests.cs b/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentTests.cs
index 6e92514ab6..4895985b20 100644
--- a/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentTests.cs
+++ b/dotnet/tests/Microsoft.Agents.UnitTests/ChatCompletion/ChatClientAgentTests.cs
@@ -156,10 +156,10 @@ public class ChatClientAgentTests
     }
 
     /// <summary>
-    /// Verify that RunAsync includes additional instructions when provided in options.
+    /// Verify that RunAsync includes base instructions in messages.
     /// </summary>
     [Fact]
-    public async Task RunAsyncIncludesAdditionalInstructionsWhenProvidedInOptionsAsync()
+    public async Task RunAsyncIncludesBaseInstructionsAsync()
     {
         // Arrange
         Mock<IChatClient> mockService = new();
@@ -174,14 +174,13 @@ public class ChatClientAgentTests
             .ReturnsAsync(new ChatResponse([new(ChatRole.Assistant, "response")]));
 
         ChatClientAgent agent = new(mockService.Object, new() { Instructions = "base instructions" });
-        var runOptions = new AgentRunOptions { AdditionalInstructions = "additional instructions" };
+        var runOptions = new AgentRunOptions();
 
         // Act
         await agent.RunAsync([new(ChatRole.User, "test")], options: runOptions);
 
         // Assert
         Assert.Contains(capturedMessages, m => m.Text == "base instructions" && m.Role == ChatRole.System);
-        Assert.Contains(capturedMessages, m => m.Text == "additional instructions" && m.Role == ChatRole.System);
         Assert.Contains(capturedMessages, m => m.Text == "test" && m.Role == ChatRole.User);
     }
 
@@ -759,18 +758,21 @@ public class ChatClientAgentTests
             MaxOutputTokens = 100,
             Temperature = 0.7f,
             TopP = 0.9f,
-            ModelId = "agent-model"
+            ModelId = "agent-model",
+            AdditionalProperties = new AdditionalPropertiesDictionary() { ["key"] = "agent-value" }
         };
         var requestChatOptions = new ChatOptions
         {
             MaxOutputTokens = 200,
-            Temperature = 0.3f
+            Temperature = 0.3f,
+            AdditionalProperties = new AdditionalPropertiesDictionary() { ["key"] = "request-value" }
             // TopP and ModelId not set, should use agent values
         };
         var expectedChatOptionsMerge = new ChatOptions
         {
             MaxOutputTokens = 200, // Request value takes priority
             Temperature = 0.3f, // Request value takes priority
+            AdditionalProperties = new AdditionalPropertiesDictionary() { ["key"] = "request-value" }, // Request value takes priority
             TopP = 0.9f, // Agent value used when request doesn't specify
             ModelId = "agent-model" // Agent value used when request doesn't specify
         };
@@ -801,6 +803,8 @@ public class ChatClientAgentTests
         Assert.Equivalent(expectedChatOptionsMerge, capturedChatOptions); // Should be the same instance (modified in place)
         Assert.Equal(200, capturedChatOptions.MaxOutputTokens); // Request value takes priority
         Assert.Equal(0.3f, capturedChatOptions.Temperature); // Request value takes priority
+        Assert.NotNull(capturedChatOptions.AdditionalProperties);
+        Assert.Equal("request-value", capturedChatOptions.AdditionalProperties["key"]); // Request value takes priority
         Assert.Equal(0.9f, capturedChatOptions.TopP); // Agent value used when request doesn't specify
         Assert.Equal("agent-model", capturedChatOptions.ModelId); // Agent value used when request doesn't specify
     }
diff --git a/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantChatClientAgentRunStreamingTests.cs b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantChatClientAgentRunStreamingTests.cs
new file mode 100644
index 0000000000..78d985a6f3
--- /dev/null
+++ b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantChatClientAgentRunStreamingTests.cs
@@ -0,0 +1,9 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace OpenAIAssistant.IntegrationTests;
+
+public class OpenAIAssistantChatClientAgentRunStreamingTests() : ChatClientAgentRunStreamingTests<OpenAIAssistantFixture>(() => new())
+{
+}
diff --git a/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantChatClientAgentRunTests.cs b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantChatClientAgentRunTests.cs
new file mode 100644
index 0000000000..641e656379
--- /dev/null
+++ b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantChatClientAgentRunTests.cs
@@ -0,0 +1,9 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace OpenAIAssistant.IntegrationTests;
+
+public class OpenAIAssistantChatClientAgentRunTests() : ChatClientAgentRunTests<OpenAIAssistantFixture>(() => new())
+{
+}
diff --git a/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantFixture.cs b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantFixture.cs
index fe6ad9817b..01f6dfdd48 100644
--- a/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantFixture.cs
+++ b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantFixture.cs
@@ -3,8 +3,8 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using AgentConformance.IntegrationTests;
 using AgentConformance.IntegrationTests.Support;
-using AgentConformanceTests;
 using Microsoft.Agents;
 using Microsoft.Extensions.AI;
 using OpenAI;
@@ -15,8 +15,10 @@ namespace OpenAIAssistant.IntegrationTests;
 
 #pragma warning disable OPENAI001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
 
-public class OpenAIAssistantFixture : AgentFixture
+public class OpenAIAssistantFixture : IChatClientAgentFixture
 {
+    private static readonly OpenAIConfiguration s_config = TestConfiguration.LoadSection<OpenAIConfiguration>();
+
 #pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
     private AssistantClient? _assistantClient;
     private Assistant? _assistant;
@@ -24,9 +26,11 @@ public class OpenAIAssistantFixture : AgentFixture
     private Agent _agent;
 #pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
 
-    public override Agent Agent => this._agent;
+    public Agent Agent => this._agent;
 
-    public override async Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread)
+    public IChatClient ChatClient => this._chatClient;
+
+    public async Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread)
     {
         if (thread is not ChatClientAgentThread chatClientThread)
         {
@@ -49,7 +53,26 @@ public class OpenAIAssistantFixture : AgentFixture
         return messages;
     }
 
-    public override Task DeleteThreadAsync(AgentThread thread)
+    public async Task<ChatClientAgent> CreateAgentWithInstructionsAsync(string instructions)
+    {
+        var assistant =
+            await this._assistantClient!.CreateAssistantAsync(
+                s_config.ChatModelId!,
+                new AssistantCreationOptions()
+                {
+                    Name = "HelpfulAssistant",
+                    Instructions = instructions
+                });
+
+        return new ChatClientAgent(this._assistantClient.AsIChatClient(assistant.Value.Id), new() { Id = assistant.Value.Id });
+    }
+
+    public Task DeleteAgentAsync(ChatClientAgent agent)
+    {
+        return this._assistantClient!.DeleteAssistantAsync(agent.Id);
+    }
+
+    public Task DeleteThreadAsync(AgentThread thread)
     {
         if (thread?.Id is not null)
         {
@@ -59,16 +82,14 @@ public class OpenAIAssistantFixture : AgentFixture
         return Task.CompletedTask;
     }
 
-    public override async Task InitializeAsync()
+    public async Task InitializeAsync()
     {
-        var config = TestConfiguration.LoadSection<OpenAIConfiguration>();
-
-        var client = new OpenAIClient(config.ApiKey);
+        var client = new OpenAIClient(s_config.ApiKey);
         this._assistantClient = client.GetAssistantClient();
 
         this._assistant =
             await this._assistantClient.CreateAssistantAsync(
-                config.ChatModelId!,
+                s_config.ChatModelId!,
                 new AssistantCreationOptions()
                 {
                     Name = "HelpfulAssistant",
@@ -80,7 +101,7 @@ public class OpenAIAssistantFixture : AgentFixture
         this._agent = new ChatClientAgent(this._chatClient);
     }
 
-    public override Task DisposeAsync()
+    public Task DisposeAsync()
     {
         if (this._assistantClient is not null && this._assistant is not null)
         {
diff --git a/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantInvokeTests.cs b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantIRunTests.cs
similarity index 60%
rename from dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantInvokeTests.cs
rename to dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantIRunTests.cs
index c863a5e6a2..736c9fe063 100644
--- a/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantInvokeTests.cs
+++ b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantIRunTests.cs
@@ -4,6 +4,6 @@ using AgentConformance.IntegrationTests;
 
 namespace OpenAIAssistant.IntegrationTests;
 
-public class OpenAIAssistantInvokeTests() : RunAsyncTests<OpenAIAssistantFixture>(() => new())
+public class OpenAIAssistantIRunTests() : RunTests<OpenAIAssistantFixture>(() => new())
 {
 }
diff --git a/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantInvokeStreamingTests.cs b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantRunStreamingTests.cs
similarity index 56%
rename from dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantInvokeStreamingTests.cs
rename to dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantRunStreamingTests.cs
index 37be58090d..355fe8e549 100644
--- a/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantInvokeStreamingTests.cs
+++ b/dotnet/tests/OpenAIAssistant.IntegrationTests/OpenAIAssistantRunStreamingTests.cs
@@ -4,6 +4,6 @@ using AgentConformance.IntegrationTests;
 
 namespace OpenAIAssistant.IntegrationTests;
 
-public class OpenAIAssistantInvokeStreamingTests() : RunStreamingAsyncTests<OpenAIAssistantFixture>(() => new())
+public class OpenAIAssistantRunStreamingTests() : RunStreamingTests<OpenAIAssistantFixture>(() => new())
 {
 }
diff --git a/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionChatClientAgentRunStreamingTests.cs b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionChatClientAgentRunStreamingTests.cs
new file mode 100644
index 0000000000..bcb2824a5a
--- /dev/null
+++ b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionChatClientAgentRunStreamingTests.cs
@@ -0,0 +1,9 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace OpenAIChatCompletion.IntegrationTests;
+
+public class OpenAIChatCompletionChatClientAgentRunStreamingTests() : ChatClientAgentRunStreamingTests<OpenAIChatCompletionFixture>(() => new())
+{
+}
diff --git a/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionChatClientAgentRunTests.cs b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionChatClientAgentRunTests.cs
new file mode 100644
index 0000000000..5602204af8
--- /dev/null
+++ b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionChatClientAgentRunTests.cs
@@ -0,0 +1,9 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace OpenAIChatCompletion.IntegrationTests;
+
+public class OpenAIChatCompletionChatClientAgentRunTests() : ChatClientAgentRunTests<OpenAIChatCompletionFixture>(() => new())
+{
+}
diff --git a/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionFixture.cs b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionFixture.cs
index cdfb7c6555..a51e03da13 100644
--- a/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionFixture.cs
+++ b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionFixture.cs
@@ -4,8 +4,8 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
+using AgentConformance.IntegrationTests;
 using AgentConformance.IntegrationTests.Support;
-using AgentConformanceTests;
 using Microsoft.Agents;
 using Microsoft.Extensions.AI;
 using OpenAI;
@@ -13,16 +13,20 @@ using Shared.IntegrationTests;
 
 namespace OpenAIChatCompletion.IntegrationTests;
 
-public class OpenAIChatCompletionFixture : AgentFixture
+public class OpenAIChatCompletionFixture : IChatClientAgentFixture
 {
+    private static readonly OpenAIConfiguration s_config = TestConfiguration.LoadSection<OpenAIConfiguration>();
+
 #pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
     private IChatClient _chatClient;
     private Agent _agent;
 #pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
 
-    public override Agent Agent => this._agent;
+    public Agent Agent => this._agent;
 
-    public override async Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread)
+    public IChatClient ChatClient => this._chatClient;
+
+    public async Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread)
     {
         if (thread is not ChatClientAgentThread chatClientThread)
         {
@@ -32,18 +36,35 @@ public class OpenAIChatCompletionFixture : AgentFixture
         return await chatClientThread.GetMessagesAsync().ToListAsync();
     }
 
-    public override Task DeleteThreadAsync(AgentThread thread)
+    public Task<ChatClientAgent> CreateAgentWithInstructionsAsync(string instructions)
+    {
+        this._chatClient = new OpenAIClient(s_config.ApiKey)
+            .GetChatClient(s_config.ChatModelId)
+            .AsIChatClient();
+
+        return Task.FromResult(new ChatClientAgent(this._chatClient, new()
+        {
+            Name = "HelpfulAssistant",
+            Instructions = instructions,
+        }));
+    }
+
+    public Task DeleteAgentAsync(ChatClientAgent agent)
+    {
+        // Chat Completion does not require/support deleting agents, so this is a no-op.
+        return Task.CompletedTask;
+    }
+
+    public Task DeleteThreadAsync(AgentThread thread)
     {
         // Chat Completion does not require/support deleting threads, so this is a no-op.
         return Task.CompletedTask;
     }
 
-    public override Task InitializeAsync()
+    public Task InitializeAsync()
     {
-        var config = TestConfiguration.LoadSection<OpenAIConfiguration>();
-
-        this._chatClient = new OpenAIClient(config.ApiKey)
-            .GetChatClient(config.ChatModelId)
+        this._chatClient = new OpenAIClient(s_config.ApiKey)
+            .GetChatClient(s_config.ChatModelId)
             .AsIChatClient();
 
         this._agent =
@@ -56,7 +77,7 @@ public class OpenAIChatCompletionFixture : AgentFixture
         return Task.CompletedTask;
     }
 
-    public override Task DisposeAsync()
+    public Task DisposeAsync()
     {
         this._chatClient.Dispose();
         return Task.CompletedTask;
diff --git a/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionInvokeStreamingTests.cs b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionRunStreamingTests.cs
similarity index 54%
rename from dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionInvokeStreamingTests.cs
rename to dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionRunStreamingTests.cs
index ee7cac8327..dac192ba5d 100644
--- a/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionInvokeStreamingTests.cs
+++ b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionRunStreamingTests.cs
@@ -4,6 +4,6 @@ using AgentConformance.IntegrationTests;
 
 namespace OpenAIChatCompletion.IntegrationTests;
 
-public class OpenAIChatCompletionInvokeStreamingTests() : RunStreamingAsyncTests<OpenAIChatCompletionFixture>(() => new())
+public class OpenAIChatCompletionRunStreamingTests() : RunStreamingTests<OpenAIChatCompletionFixture>(() => new())
 {
 }
diff --git a/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionInvokeTests.cs b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionRunTests.cs
similarity index 58%
rename from dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionInvokeTests.cs
rename to dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionRunTests.cs
index 45e7993350..3de2d9b90d 100644
--- a/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionInvokeTests.cs
+++ b/dotnet/tests/OpenAIChatCompletion.IntegrationTests/OpenAIChatCompletionRunTests.cs
@@ -4,6 +4,6 @@ using AgentConformance.IntegrationTests;
 
 namespace OpenAIChatCompletion.IntegrationTests;
 
-public class OpenAIChatCompletionInvokeTests() : RunAsyncTests<OpenAIChatCompletionFixture>(() => new())
+public class OpenAIChatCompletionRunTests() : RunTests<OpenAIChatCompletionFixture>(() => new())
 {
 }
diff --git a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseChatClientAgentRunStreamingTests.cs b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseChatClientAgentRunStreamingTests.cs
new file mode 100644
index 0000000000..171eecfd47
--- /dev/null
+++ b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseChatClientAgentRunStreamingTests.cs
@@ -0,0 +1,13 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace OpenAIResponse.IntegrationTests;
+
+public class OpenAIResponseStoreTrueChatClientAgentRunStreamingTests() : ChatClientAgentRunStreamingTests<OpenAIResponseFixture>(() => new(store: true))
+{
+}
+
+public class OpenAIResponseStoreFalseChatClientAgentRunStreamingTests() : ChatClientAgentRunStreamingTests<OpenAIResponseFixture>(() => new(store: false))
+{
+}
diff --git a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseChatClientAgentRunTests.cs b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseChatClientAgentRunTests.cs
new file mode 100644
index 0000000000..d146ac7dbe
--- /dev/null
+++ b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseChatClientAgentRunTests.cs
@@ -0,0 +1,13 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace OpenAIResponse.IntegrationTests;
+
+public class OpenAIResponseStoreTrueChatClientAgentRunTests() : ChatClientAgentRunTests<OpenAIResponseFixture>(() => new(store: true))
+{
+}
+
+public class OpenAIResponseStoreFalseChatClientAgentRunTests() : ChatClientAgentRunTests<OpenAIResponseFixture>(() => new(store: false))
+{
+}
diff --git a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseFixture.cs b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseFixture.cs
index c1a7b9edbf..45b19ebeb9 100644
--- a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseFixture.cs
+++ b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseFixture.cs
@@ -4,8 +4,8 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
+using AgentConformance.IntegrationTests;
 using AgentConformance.IntegrationTests.Support;
-using AgentConformanceTests;
 using Microsoft.Agents;
 using Microsoft.Extensions.AI;
 using OpenAI;
@@ -14,17 +14,21 @@ using Shared.IntegrationTests;
 
 namespace OpenAIResponse.IntegrationTests;
 
-public class OpenAIResponseFixture(bool store) : AgentFixture
+public class OpenAIResponseFixture(bool store) : IChatClientAgentFixture
 {
+    private static readonly OpenAIConfiguration s_config = TestConfiguration.LoadSection<OpenAIConfiguration>();
+
 #pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
     private OpenAIResponseClient _openAIResponseClient;
     private IChatClient _chatClient;
     private Agent _agent;
 #pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
 
-    public override Agent Agent => this._agent;
+    public Agent Agent => this._agent;
 
-    public override async Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread)
+    public IChatClient ChatClient => this._chatClient;
+
+    public async Task<List<ChatMessage>> GetChatHistoryAsync(AgentThread thread)
     {
         if (thread is not ChatClientAgentThread chatClientThread)
         {
@@ -68,18 +72,37 @@ public class OpenAIResponseFixture(bool store) : AgentFixture
         throw new NotSupportedException("This test currently only supports text messages");
     }
 
-    public override Task DeleteThreadAsync(AgentThread thread)
+    public Task<ChatClientAgent> CreateAgentWithInstructionsAsync(string instructions)
+    {
+        var options = new ChatClientAgentOptions
+        {
+            Name = "HelpfulAssistant",
+            Instructions = instructions,
+            ChatOptions = new ChatOptions
+            {
+                RawRepresentationFactory = new Func<IChatClient, object>((_) => new ResponseCreationOptions() { StoredOutputEnabled = store })
+            },
+        };
+
+        return Task.FromResult(new ChatClientAgent(this._chatClient, options));
+    }
+
+    public Task DeleteAgentAsync(ChatClientAgent agent)
+    {
+        // Chat Completion does not require/support deleting agents, so this is a no-op.
+        return Task.CompletedTask;
+    }
+
+    public Task DeleteThreadAsync(AgentThread thread)
     {
         // Chat Completion does not require/support deleting threads, so this is a no-op.
         return Task.CompletedTask;
     }
 
-    public override Task InitializeAsync()
+    public Task InitializeAsync()
     {
-        var config = TestConfiguration.LoadSection<OpenAIConfiguration>();
-
-        this._openAIResponseClient = new OpenAIClient(config.ApiKey)
-            .GetOpenAIResponseClient(config.ChatModelId);
+        this._openAIResponseClient = new OpenAIClient(s_config.ApiKey)
+            .GetOpenAIResponseClient(s_config.ChatModelId);
         this._chatClient = this._openAIResponseClient
             .AsIChatClient();
 
@@ -99,7 +122,7 @@ public class OpenAIResponseFixture(bool store) : AgentFixture
         return Task.CompletedTask;
     }
 
-    public override Task DisposeAsync()
+    public Task DisposeAsync()
     {
         this._chatClient.Dispose();
         return Task.CompletedTask;
diff --git a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseInvokeStreamingTests.cs b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseInvokeStreamingTests.cs
deleted file mode 100644
index 49d13af615..0000000000
--- a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseInvokeStreamingTests.cs
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using AgentConformance.IntegrationTests;
-
-namespace OpenAIResponse.IntegrationTests;
-
-public class OpenAIResponseStoreTrueInvokeStreamingTests() : RunStreamingAsyncTests<OpenAIResponseFixture>(() => new(store: true))
-{
-}
-
-public class OpenAIResponseStoreFalseInvokeStreamingTests() : RunStreamingAsyncTests<OpenAIResponseFixture>(() => new(store: false))
-{
-}
diff --git a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseInvokeTests.cs b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseInvokeTests.cs
deleted file mode 100644
index a0135b3551..0000000000
--- a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseInvokeTests.cs
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright (c) Microsoft. All rights reserved.
-
-using AgentConformance.IntegrationTests;
-
-namespace OpenAIResponse.IntegrationTests;
-
-public class OpenAIResponseStoreTrueInvokeTests() : RunAsyncTests<OpenAIResponseFixture>(() => new(store: true))
-{
-}
-
-public class OpenAIResponseStoreFalseInvokeTests() : RunAsyncTests<OpenAIResponseFixture>(() => new(store: false))
-{
-}
diff --git a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseRunStreamingTests.cs b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseRunStreamingTests.cs
new file mode 100644
index 0000000000..00f8a04a68
--- /dev/null
+++ b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseRunStreamingTests.cs
@@ -0,0 +1,13 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace OpenAIResponse.IntegrationTests;
+
+public class OpenAIResponseStoreTrueRunStreamingTests() : RunStreamingTests<OpenAIResponseFixture>(() => new(store: true))
+{
+}
+
+public class OpenAIResponseStoreFalseRunStreamingTests() : RunStreamingTests<OpenAIResponseFixture>(() => new(store: false))
+{
+}
diff --git a/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseRunTests.cs b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseRunTests.cs
new file mode 100644
index 0000000000..1a8fbb3286
--- /dev/null
+++ b/dotnet/tests/OpenAIResponse.IntegrationTests/OpenAIResponseRunTests.cs
@@ -0,0 +1,13 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using AgentConformance.IntegrationTests;
+
+namespace OpenAIResponse.IntegrationTests;
+
+public class OpenAIResponseStoreTrueRunTests() : RunTests<OpenAIResponseFixture>(() => new(store: true))
+{
+}
+
+public class OpenAIResponseStoreFalseRunTests() : RunTests<OpenAIResponseFixture>(() => new(store: false))
+{
+}