.NET: Add dedicated Foundry.Hosting UnitTest project

dotnet/agent-framework-dotnet.slnx

@@ -592,6 +592,7 @@
     <Project Path="tests/Microsoft.Agents.AI.DevUI.UnitTests/Microsoft.Agents.AI.DevUI.UnitTests.csproj" />
     <Project Path="tests/Microsoft.Agents.AI.DurableTask.UnitTests/Microsoft.Agents.AI.DurableTask.UnitTests.csproj" />
     <Project Path="tests/Microsoft.Agents.AI.Foundry.UnitTests/Microsoft.Agents.AI.Foundry.UnitTests.csproj" />
+    <Project Path="tests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests.csproj" />
     <Project Path="tests/Microsoft.Agents.AI.GitHub.Copilot.UnitTests/Microsoft.Agents.AI.GitHub.Copilot.UnitTests.csproj" />
     <Project Path="tests/Microsoft.Agents.AI.Hosting.A2A.UnitTests/Microsoft.Agents.AI.Hosting.A2A.UnitTests.csproj" />
     <Project Path="tests/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore.UnitTests/Microsoft.Agents.AI.Hosting.AGUI.AspNetCore.UnitTests.csproj" />

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/HostedAgentUserAgentPolicy.cs

@@ -19,7 +19,7 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// </para>
 /// <para>
 /// This policy is added at request time (per-call <see cref="PipelinePosition"/>)
-/// by <see cref="DelegatingResponsesClient"/> when invoking the wrapped
+/// by <see cref="UserAgentResponsesClient"/> when invoking the wrapped
 /// <see cref="OpenAI.Responses.ResponsesClient"/>. It is only registered when an agent is
 /// resolved by the Foundry hosting layer.
 /// </para>

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/Microsoft.Agents.AI.Foundry.Hosting.csproj

@@ -44,7 +44,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <InternalsVisibleTo Include="Microsoft.Agents.AI.Foundry.UnitTests" />
+    <InternalsVisibleTo Include="Microsoft.Agents.AI.Foundry.Hosting.UnitTests" />
     <InternalsVisibleTo Include="DynamicProxyGenAssembly2" />
   </ItemGroup>
 

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/ServiceCollectionExtensions.cs

@@ -210,7 +210,7 @@ internal static AIAgent ApplyOpenTelemetry(AIAgent agent)
 
     /// <summary>
     /// Attempts to wrap the agent's underlying <see cref="ResponsesClient"/>
-    /// with a <see cref="DelegatingResponsesClient"/> so every outgoing Responses-API request
+    /// with a <see cref="UserAgentResponsesClient"/> so every outgoing Responses-API request
     /// carries the hosted-agent <c>User-Agent</c> segment.
     /// </summary>
     /// <remarks>
@@ -219,7 +219,7 @@ internal static AIAgent ApplyOpenTelemetry(AIAgent agent)
     /// <list type="bullet">
     /// <item><description><paramref name="agent"/> exposes no <see cref="IChatClient"/>;</description></item>
     /// <item><description>the chat client is not backed by MEAI's internal <c>OpenAIResponsesChatClient</c> (e.g., a non-OpenAI provider or a custom impl);</description></item>
-    /// <item><description>the inner <see cref="ResponsesClient"/> is already a <see cref="DelegatingResponsesClient"/>.</description></item>
+    /// <item><description>the inner <see cref="ResponsesClient"/> is already a <see cref="UserAgentResponsesClient"/>.</description></item>
     /// </list>
     /// </para>
     /// <para>
@@ -261,12 +261,12 @@ internal static AIAgent TryApplyUserAgent(AIAgent agent)
         }
 
         var current = field.GetValue(meaiInstance) as ResponsesClient;
-        if (current is null or DelegatingResponsesClient)
+        if (current is null or UserAgentResponsesClient)
         {
             return agent;
         }
 
-        field.SetValue(meaiInstance, new DelegatingResponsesClient(current));
+        field.SetValue(meaiInstance, new UserAgentResponsesClient(current));
         return agent;
     }
 

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/DelegatingResponsesClient.cs → dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/UserAgentResponsesClient.cs

@@ -33,11 +33,11 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// never expected to run; the throwing transport surfaces any unexpected escape route loudly.
 /// </para>
 /// </remarks>
-internal sealed class DelegatingResponsesClient : ResponsesClient
+internal sealed class UserAgentResponsesClient : ResponsesClient
 {
     private readonly ResponsesClient _inner;
 
-    public DelegatingResponsesClient(ResponsesClient inner)
+    public UserAgentResponsesClient(ResponsesClient inner)
         : base(BuildDummyPipeline(), new OpenAIClientOptions { Endpoint = inner?.Endpoint })
     {
         this._inner = inner ?? throw new ArgumentNullException(nameof(inner));
@@ -104,7 +104,7 @@ private static ClientPipeline BuildDummyPipeline()
     private sealed class ThrowingTransport : PipelineTransport
     {
         private const string Message =
-            "DelegatingResponsesClient transport invoked bypassed the override-and-delegate design. This exception should be unreachable and should never be thrown following the correct usage of DelegatingResponsesClient.";
+            "UserAgentResponsesClient transport invoked bypassed the override-and-delegate design. This exception should be unreachable and should never be thrown following the correct usage of UserAgentResponsesClient.";
 
         protected override PipelineMessage CreateMessageCore() => throw new InvalidOperationException(Message);
         protected override void ProcessCore(PipelineMessage message) => throw new InvalidOperationException(Message);

dotnet/src/Microsoft.Agents.AI.Foundry/Microsoft.Agents.AI.Foundry.csproj

@@ -53,6 +53,7 @@
 
   <ItemGroup>
     <InternalsVisibleTo Include="Microsoft.Agents.AI.Foundry.UnitTests" />
+    <InternalsVisibleTo Include="Microsoft.Agents.AI.Foundry.Hosting.UnitTests" />
     <InternalsVisibleTo Include="DynamicProxyGenAssembly2" />
   </ItemGroup>
 

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/AgentFrameworkResponseHandlerTelemetryTests.cs → dotnet/tests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests/AgentFrameworkResponseHandlerTelemetryTests.cs

@@ -10,7 +10,6 @@
 using System.Threading.Tasks;
 using Azure.AI.AgentServer.Responses;
 using Azure.AI.AgentServer.Responses.Models;
-using Microsoft.Agents.AI.Foundry.Hosting;
 using Microsoft.Extensions.AI;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging.Abstractions;
@@ -19,7 +18,7 @@
 using OpenTelemetry.Trace;
 using MeaiTextContent = Microsoft.Extensions.AI.TextContent;
 
-namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
+namespace Microsoft.Agents.AI.Foundry.Hosting.UnitTests;
 
 /// <summary>
 /// Tests that verify OTel spans are actually emitted and captured through the

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/AgentFrameworkResponseHandlerTests.cs → dotnet/tests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests/AgentFrameworkResponseHandlerTests.cs

@@ -9,15 +9,14 @@
 using System.Threading.Tasks;
 using Azure.AI.AgentServer.Responses;
 using Azure.AI.AgentServer.Responses.Models;
-using Microsoft.Agents.AI.Foundry.Hosting;
 using Microsoft.Extensions.AI;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
 using Moq;
 using MeaiTextContent = Microsoft.Extensions.AI.TextContent;
 
-namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
+namespace Microsoft.Agents.AI.Foundry.Hosting.UnitTests;
 
 public class AgentFrameworkResponseHandlerTests
 {

dotnet/tests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests/AgentFrameworkResponseHandlerWorkflowTests.cs

@@ -0,0 +1,212 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using Azure.AI.AgentServer.Responses;
+using Azure.AI.AgentServer.Responses.Models;
+using Microsoft.Agents.AI.Workflows;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Abstractions;
+using Moq;
+
+namespace Microsoft.Agents.AI.Foundry.Hosting.UnitTests;
+
+/// <summary>
+/// Unit tests for <see cref="AgentFrameworkResponseHandler"/> that verify behavior
+/// when the registered agent is a workflow-backed <see cref="AIAgent"/>. These exercise
+/// real workflow builders and the in-process execution environment to drive the handler
+/// through realistic streaming event patterns.
+/// </summary>
+public class AgentFrameworkResponseHandlerWorkflowTests
+{
+    [Fact]
+    public async Task SequentialWorkflow_SingleAgent_ProducesTextOutputAsync()
+    {
+        // Arrange: single-agent sequential workflow
+        var echoAgent = new StreamingTextAgent("echo", "Hello from the workflow!");
+        var workflow = AgentWorkflowBuilder.BuildSequential("test-sequential", echoAgent);
+        var workflowAgent = workflow.AsAIAgent(
+            id: "workflow-agent",
+            name: "Test Workflow",
+            executionEnvironment: InProcessExecution.OffThread,
+            includeExceptionDetails: true);
+
+        var (handler, request, context) = CreateHandlerWithAgent(workflowAgent, "Hello");
+
+        // Act
+        var events = await CollectEventsAsync(handler, request, context);
+
+        // Assert: should have lifecycle events + at least one text output + terminal
+        Assert.IsType<ResponseCreatedEvent>(events[0]);
+        Assert.IsType<ResponseInProgressEvent>(events[1]);
+        Assert.True(events.Count >= 4, $"Expected at least 4 events, got {events.Count}");
+
+        var lastEvent = events[^1];
+        Assert.True(
+            lastEvent is ResponseCompletedEvent || lastEvent is ResponseFailedEvent,
+            $"Expected terminal event, got {lastEvent.GetType().Name}");
+    }
+
+    [Fact]
+    public async Task SequentialWorkflow_TwoAgents_ProducesOutputFromBothAsync()
+    {
+        // Arrange: two agents in sequence
+        var agent1 = new StreamingTextAgent("agent1", "First agent says hello");
+        var agent2 = new StreamingTextAgent("agent2", "Second agent says goodbye");
+        var workflow = AgentWorkflowBuilder.BuildSequential("test-sequential-2", agent1, agent2);
+        var workflowAgent = workflow.AsAIAgent(
+            id: "seq-workflow",
+            name: "Sequential Workflow",
+            executionEnvironment: InProcessExecution.OffThread,
+            includeExceptionDetails: true);
+
+        var (handler, request, context) = CreateHandlerWithAgent(workflowAgent, "Process this");
+
+        // Act
+        var events = await CollectEventsAsync(handler, request, context);
+
+        // Assert: should have workflow action events for executor lifecycle
+        var lastEvent = events[^1];
+        Assert.True(
+            lastEvent is ResponseCompletedEvent || lastEvent is ResponseFailedEvent,
+            $"Expected terminal event, got {lastEvent.GetType().Name}");
+
+        // Should have output item events (either text messages or workflow actions)
+        Assert.True(events.OfType<ResponseOutputItemAddedEvent>().Any(),
+            "Expected at least one output item from the workflow");
+    }
+
+    [Fact]
+    public async Task Workflow_AgentThrowsException_ProducesErrorOutputAsync()
+    {
+        // Arrange: workflow with an agent that throws
+        var throwingAgent = new ThrowingStreamingAgent("thrower", new InvalidOperationException("Agent crashed"));
+        var workflow = AgentWorkflowBuilder.BuildSequential("test-error", throwingAgent);
+        var workflowAgent = workflow.AsAIAgent(
+            id: "error-workflow",
+            name: "Error Workflow",
+            executionEnvironment: InProcessExecution.OffThread,
+            includeExceptionDetails: true);
+
+        var (handler, request, context) = CreateHandlerWithAgent(workflowAgent, "Trigger error");
+
+        // Act
+        var events = await CollectEventsAsync(handler, request, context);
+
+        // Assert: should have lifecycle events + error/failure indicator
+        Assert.IsType<ResponseCreatedEvent>(events[0]);
+        Assert.IsType<ResponseInProgressEvent>(events[1]);
+
+        var lastEvent = events[^1];
+        // Workflow errors surface as either Failed or Completed (depending on error handling)
+        Assert.True(
+            lastEvent is ResponseCompletedEvent || lastEvent is ResponseFailedEvent,
+            $"Expected terminal event, got {lastEvent.GetType().Name}");
+    }
+
+    [Fact]
+    public async Task Workflow_ExecutorEvents_ProduceWorkflowActionItemsAsync()
+    {
+        // Arrange
+        var agent = new StreamingTextAgent("test-agent", "Result");
+        var workflow = AgentWorkflowBuilder.BuildSequential("test-actions", agent);
+        var workflowAgent = workflow.AsAIAgent(
+            id: "actions-workflow",
+            name: "Actions Workflow",
+            executionEnvironment: InProcessExecution.OffThread);
+
+        var (handler, request, context) = CreateHandlerWithAgent(workflowAgent, "Hello");
+
+        // Act
+        var events = await CollectEventsAsync(handler, request, context);
+
+        // Assert: workflow should produce OutputItemAdded events for executor lifecycle
+        var addedEvents = events.OfType<ResponseOutputItemAddedEvent>().ToList();
+        Assert.True(addedEvents.Count >= 1,
+            $"Expected at least 1 output item added event, got {addedEvents.Count}");
+    }
+
+    [Fact]
+    public async Task WorkflowAgent_RegisteredWithKey_ResolvesCorrectlyAsync()
+    {
+        // Arrange: workflow agent registered with a keyed service name
+        var agent = new StreamingTextAgent("inner", "Keyed workflow response");
+        var workflow = AgentWorkflowBuilder.BuildSequential("keyed-wf", agent);
+        var workflowAgent = workflow.AsAIAgent(
+            id: "keyed-workflow",
+            name: "Keyed Workflow",
+            executionEnvironment: InProcessExecution.OffThread);
+
+        var services = new ServiceCollection();
+        services.AddSingleton<AgentSessionStore>(new InMemoryAgentSessionStore());
+        services.AddKeyedSingleton("my-workflow", workflowAgent);
+        var sp = services.BuildServiceProvider();
+
+        var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
+        var request = new CreateResponse { Model = "test", AgentReference = new AgentReference("my-workflow") };
+        request.Input = CreateUserInput("Test keyed workflow");
+        var mockContext = CreateMockContext();
+
+        // Act
+        var events = await CollectEventsAsync(handler, request, mockContext.Object);
+
+        // Assert
+        Assert.IsType<ResponseCreatedEvent>(events[0]);
+        Assert.True(events.Count >= 3, $"Expected at least 3 events, got {events.Count}");
+    }
+
+    private static (AgentFrameworkResponseHandler handler, CreateResponse request, ResponseContext context)
+        CreateHandlerWithAgent(AIAgent agent, string userMessage)
+    {
+        var services = new ServiceCollection();
+        services.AddSingleton<AgentSessionStore>(new InMemoryAgentSessionStore());
+        services.AddSingleton(agent);
+        services.AddSingleton<ILogger<AgentFrameworkResponseHandler>>(NullLogger<AgentFrameworkResponseHandler>.Instance);
+        var sp = services.BuildServiceProvider();
+
+        var handler = new AgentFrameworkResponseHandler(sp, NullLogger<AgentFrameworkResponseHandler>.Instance);
+        var request = new CreateResponse { Model = "test" };
+        request.Input = CreateUserInput(userMessage);
+        var mockContext = CreateMockContext();
+
+        return (handler, request, mockContext.Object);
+    }
+
+    private static BinaryData CreateUserInput(string text)
+    {
+        return BinaryData.FromObjectAsJson(new[]
+        {
+            new { type = "message", id = "msg_in_1", status = "completed", role = "user",
+                  content = new[] { new { type = "input_text", text } }
+            }
+        });
+    }
+
+    private static Mock<ResponseContext> CreateMockContext()
+    {
+        var mock = new Mock<ResponseContext>("resp_" + new string('0', 46)) { CallBase = true };
+        mock.Setup(x => x.GetHistoryAsync(It.IsAny<CancellationToken>()))
+            .ReturnsAsync(Array.Empty<OutputItem>());
+        mock.Setup(x => x.GetInputItemsAsync(It.IsAny<bool>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(Array.Empty<Item>());
+        return mock;
+    }
+
+    private static async Task<List<ResponseStreamEvent>> CollectEventsAsync(
+        AgentFrameworkResponseHandler handler,
+        CreateResponse request,
+        ResponseContext context)
+    {
+        var events = new List<ResponseStreamEvent>();
+        await foreach (var evt in handler.CreateAsync(request, context, CancellationToken.None))
+        {
+            events.Add(evt);
+        }
+
+        return events;
+    }
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests/FakeAuthenticationTokenProvider.cs

@@ -0,0 +1,28 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.Agents.AI.Foundry.Hosting.UnitTests;
+
+internal sealed class FakeAuthenticationTokenProvider : AuthenticationTokenProvider
+{
+    public override GetTokenOptions? CreateTokenOptions(IReadOnlyDictionary<string, object> properties)
+    {
+        return new GetTokenOptions(new Dictionary<string, object>());
+    }
+
+    public override AuthenticationToken GetToken(GetTokenOptions options, CancellationToken cancellationToken)
+    {
+        return new AuthenticationToken("token-value", "token-type", DateTimeOffset.UtcNow.AddHours(1));
+    }
+
+    public override ValueTask<AuthenticationToken> GetTokenAsync(GetTokenOptions options, CancellationToken cancellationToken)
+    {
+        return new ValueTask<AuthenticationToken>(this.GetToken(options, cancellationToken));
+    }
+}

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/FoundryAIToolExtensionsTests.cs → dotnet/tests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests/FoundryAIToolExtensionsTests.cs

@@ -1,9 +1,8 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 using System;
-using Microsoft.Agents.AI.Foundry.Hosting;
 
-namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
+namespace Microsoft.Agents.AI.Foundry.Hosting.UnitTests;
 
 public class FoundryAIToolExtensionsTests
 {

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/FoundryToolboxBearerTokenHandlerTests.cs → dotnet/tests/Microsoft.Agents.AI.Foundry.Hosting.UnitTests/FoundryToolboxBearerTokenHandlerTests.cs

@@ -6,10 +6,9 @@
 using System.Threading;
 using System.Threading.Tasks;
 using Azure.Core;
-using Microsoft.Agents.AI.Foundry.Hosting;
 using Moq;
 
-namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
+namespace Microsoft.Agents.AI.Foundry.Hosting.UnitTests;
 
 public class FoundryToolboxBearerTokenHandlerTests
 {