address copilot initial feedback

dotnet/samples/05-end-to-end/A2AClientServer/A2AServer/HostAgentFactory.cs

@@ -159,14 +159,14 @@ internal static class HostAgentFactory
         agentInterfaces.AddRange(agentUrls.Select(url => new AgentInterface
         {
             Url = url,
-            ProtocolBinding = "JSONRPC",
+            ProtocolBinding = ProtocolBindingNames.JsonRpc,
             ProtocolVersion = "1.0",
         }));
 
         agentInterfaces.AddRange(agentUrls.Select(url => new AgentInterface
         {
             Url = url,
-            ProtocolBinding = "HTTP+JSON",
+            ProtocolBinding = ProtocolBindingNames.HttpJson,
             ProtocolVersion = "1.0",
         }));
 

dotnet/samples/05-end-to-end/AgentWebChat/AgentWebChat.AgentHost/Program.cs

@@ -1,6 +1,5 @@
 // Copyright (c) Microsoft. All rights reserved.
 
-using A2A.AspNetCore;
 using AgentWebChat.AgentHost;
 using AgentWebChat.AgentHost.Custom;
 using AgentWebChat.AgentHost.Utilities;

dotnet/src/Microsoft.Agents.AI.Hosting.A2A.AspNetCore/A2AEndpointRouteBuilderExtensions.cs

@@ -63,7 +63,7 @@ public static class A2AEndpointRouteBuilderExtensions
     public static IEndpointConventionBuilder MapA2AHttpJson(this IEndpointRouteBuilder endpoints, string agentName, string path)
     {
         ArgumentNullException.ThrowIfNull(endpoints);
-        ArgumentException.ThrowIfNullOrEmpty(agentName);
+        ArgumentException.ThrowIfNullOrWhiteSpace(agentName);
         ArgumentException.ThrowIfNullOrWhiteSpace(path);
 
         var a2aServer = endpoints.ServiceProvider.GetKeyedService<A2AServer>(agentName)
@@ -125,7 +125,7 @@ public static class A2AEndpointRouteBuilderExtensions
     public static IEndpointConventionBuilder MapA2AJsonRpc(this IEndpointRouteBuilder endpoints, string agentName, string path)
     {
         ArgumentNullException.ThrowIfNull(endpoints);
-        ArgumentException.ThrowIfNullOrEmpty(agentName);
+        ArgumentException.ThrowIfNullOrWhiteSpace(agentName);
         ArgumentException.ThrowIfNullOrWhiteSpace(path);
 
         var a2aServer = endpoints.ServiceProvider.GetKeyedService<A2AServer>(agentName)

dotnet/src/Microsoft.Agents.AI.Hosting.A2A/A2AAgentHandler.cs

@@ -32,6 +32,9 @@ internal sealed class A2AAgentHandler : IAgentHandler
         AIHostAgent hostAgent,
         AgentRunMode runMode)
     {
+        ArgumentNullException.ThrowIfNull(hostAgent);
+        ArgumentNullException.ThrowIfNull(runMode);
+
         this._hostAgent = hostAgent;
         this._runMode = runMode;
     }

dotnet/src/Microsoft.Agents.AI.Hosting.A2A/A2AServerServiceCollectionExtensions.cs

@@ -86,7 +86,7 @@ public static class A2AServerServiceCollectionExtensions
     public static IServiceCollection AddA2AServer(this IServiceCollection services, string agentName, Action<A2AServerRegistrationOptions>? configureOptions = null)
     {
         ArgumentNullException.ThrowIfNull(services);
-        ArgumentException.ThrowIfNullOrEmpty(agentName);
+        ArgumentException.ThrowIfNullOrWhiteSpace(agentName);
 
         A2AServerRegistrationOptions? options = null;
         if (configureOptions is not null)

dotnet/src/Microsoft.Agents.AI.Hosting.A2A/AgentRunMode.cs

@@ -2,6 +2,7 @@
 
 using System;
 using System.Diagnostics.CodeAnalysis;
+using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Shared.DiagnosticIds;
@@ -84,13 +85,17 @@ public sealed class AgentRunMode : IEquatable<AgentRunMode>
 
     /// <inheritdoc/>
     public bool Equals(AgentRunMode? other) =>
-        other is not null && string.Equals(this._value, other._value, StringComparison.OrdinalIgnoreCase);
+        other is not null
+        && string.Equals(this._value, other._value, StringComparison.OrdinalIgnoreCase)
+        && ReferenceEquals(this._runInBackground, other._runInBackground);
 
     /// <inheritdoc/>
     public override bool Equals(object? obj) => this.Equals(obj as AgentRunMode);
 
     /// <inheritdoc/>
-    public override int GetHashCode() => StringComparer.OrdinalIgnoreCase.GetHashCode(this._value);
+    public override int GetHashCode() => HashCode.Combine(
+        StringComparer.OrdinalIgnoreCase.GetHashCode(this._value),
+        RuntimeHelpers.GetHashCode(this._runInBackground));
 
     /// <inheritdoc/>
     public override string ToString() => this._value;

dotnet/tests/Microsoft.Agents.AI.A2A.UnitTests/A2AAgentTests.cs

@@ -760,6 +760,31 @@ public sealed class A2AAgentTests : IDisposable
         Assert.Equal(TaskId, a2aSession.TaskId);
     }
 
+    [Fact]
+    public async Task RunStreamingAsync_WithContinuationToken_WhenSubscribeFailsWithNonUnsupportedError_PropagatesWithoutFallbackAsync()
+    {
+        // Arrange
+        const string TaskId = "error-task-123";
+
+        this._handler.StreamingErrorCodeToReturn = A2AErrorCode.TaskNotFound;
+
+        var options = new AgentRunOptions { ContinuationToken = new A2AContinuationToken(TaskId) };
+
+        // Act & Assert - the A2AException should propagate directly without fallback to GetTask
+        var exception = await Assert.ThrowsAsync<A2AException>(async () =>
+        {
+            await foreach (var _ in this._agent.RunStreamingAsync([], null, options))
+            {
+            }
+        });
+
+        Assert.Equal(A2AErrorCode.TaskNotFound, exception.ErrorCode);
+
+        // Assert - only SubscribeToTask was called, no fallback to GetTask
+        Assert.Single(this._handler.CapturedJsonRpcRequests);
+        Assert.Equal("SubscribeToTask", this._handler.CapturedJsonRpcRequests[0].Method);
+    }
+
     [Fact]
     public async Task RunStreamingAsync_WithContinuationToken_WhenSubscribeAndGetTaskBothFail_PropagatesExceptionAsync()
     {

dotnet/tests/Microsoft.Agents.AI.Hosting.A2A.UnitTests/A2AAgentHandlerTests.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Collections.Generic;
 using System.Runtime.CompilerServices;
+using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
 using A2A;
@@ -40,6 +41,37 @@ public sealed class A2AAgentHandlerTests
         Assert.Null(capturedOptions.AdditionalProperties);
     }
 
+    /// <summary>
+    /// Verifies that when metadata is non-empty, the options passed to RunAsync have
+    /// AdditionalProperties populated with the converted metadata values.
+    /// </summary>
+    [Fact]
+    public async Task ExecuteAsync_WhenMetadataIsNonEmpty_PassesOptionsWithAdditionalPropertiesToRunAsync()
+    {
+        // Arrange
+        AgentRunOptions? capturedOptions = null;
+        A2AAgentHandler handler = CreateHandler(CreateAgentMock(options => capturedOptions = options));
+
+        // Act
+        await InvokeExecuteAsync(handler, new RequestContext
+        {
+            TaskId = "", ContextId = "ctx", StreamingResponse = false,
+            Message = new Message { MessageId = "test-id", Role = Role.User, Parts = [new Part { Text = "Hello" }] },
+            Metadata = new Dictionary<string, JsonElement>
+            {
+                ["key1"] = JsonSerializer.SerializeToElement("value1"),
+                ["key2"] = JsonSerializer.SerializeToElement(42)
+            }
+        });
+
+        // Assert
+        Assert.NotNull(capturedOptions);
+        Assert.False(capturedOptions.AllowBackgroundResponses);
+        Assert.NotNull(capturedOptions.AdditionalProperties);
+        Assert.Equal(2, capturedOptions.AdditionalProperties.Count);
+        Assert.Equal("value1", capturedOptions.AdditionalProperties["key1"]?.ToString());
+    }
+
     /// <summary>
     /// Verifies that when the agent response has AdditionalProperties, the returned Message.Metadata contains the converted values.
     /// </summary>

dotnet/tests/Microsoft.Agents.AI.Hosting.A2A.UnitTests/A2AServerServiceCollectionExtensionsTests.cs

@@ -0,0 +1,275 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using A2A;
+using Microsoft.Extensions.AI;
+using Microsoft.Extensions.DependencyInjection;
+using Moq;
+using Moq.Protected;
+
+namespace Microsoft.Agents.AI.Hosting.A2A.UnitTests;
+
+/// <summary>
+/// Unit tests for the <see cref="A2AServerServiceCollectionExtensions"/> class.
+/// </summary>
+public sealed class A2AServerServiceCollectionExtensionsTests
+{
+    /// <summary>
+    /// Verifies that AddA2AServer with an agent name registers a keyed A2AServer
+    /// that can be resolved from the service provider.
+    /// </summary>
+    [Fact]
+    public async Task AddA2AServer_WithAgentName_ResolvesKeyedA2AServerAsync()
+    {
+        // Arrange
+        const string AgentName = "test-agent";
+        var services = new ServiceCollection();
+        services.AddKeyedSingleton(AgentName, (_, _) => CreateAgentMock(AgentName).Object);
+
+        // Act
+        services.AddA2AServer(AgentName);
+
+        // Assert
+        await using var provider = services.BuildServiceProvider();
+        var server = provider.GetKeyedService<A2AServer>(AgentName);
+        Assert.NotNull(server);
+    }
+
+    /// <summary>
+    /// Verifies that AddA2AServer with an agent instance registers a keyed A2AServer
+    /// that can be resolved from the service provider using the agent's name.
+    /// </summary>
+    [Fact]
+    public async Task AddA2AServer_WithAgentInstance_ResolvesKeyedA2AServerAsync()
+    {
+        // Arrange
+        const string AgentName = "instance-agent";
+        var agentMock = CreateAgentMock(AgentName);
+        var services = new ServiceCollection();
+
+        // Act
+        services.AddA2AServer(agentMock.Object);
+
+        // Assert
+        await using var provider = services.BuildServiceProvider();
+        var server = provider.GetKeyedService<A2AServer>(AgentName);
+        Assert.NotNull(server);
+    }
+
+    /// <summary>
+    /// Verifies that when no ITaskStore or AgentSessionStore are registered,
+    /// AddA2AServer falls back to in-memory defaults and resolves successfully.
+    /// </summary>
+    [Fact]
+    public async Task AddA2AServer_WithNoCustomStores_FallsBackToInMemoryDefaultsAsync()
+    {
+        // Arrange
+        const string AgentName = "default-stores-agent";
+        var services = new ServiceCollection();
+        services.AddKeyedSingleton(AgentName, (_, _) => CreateAgentMock(AgentName).Object);
+
+        // Act
+        services.AddA2AServer(AgentName);
+
+        // Assert - resolution succeeds without any stores registered
+        await using var provider = services.BuildServiceProvider();
+        var server = provider.GetKeyedService<A2AServer>(AgentName);
+        Assert.NotNull(server);
+    }
+
+    /// <summary>
+    /// Verifies that when a custom ITaskStore is registered, AddA2AServer uses it
+    /// instead of the default InMemoryTaskStore.
+    /// </summary>
+    [Fact]
+    public async Task AddA2AServer_WithCustomTaskStore_ResolvesSuccessfullyAsync()
+    {
+        // Arrange
+        const string AgentName = "custom-taskstore-agent";
+        var services = new ServiceCollection();
+        services.AddKeyedSingleton(AgentName, (_, _) => CreateAgentMock(AgentName).Object);
+
+        var mockTaskStore = new Mock<ITaskStore>();
+        services.AddKeyedSingleton(AgentName, mockTaskStore.Object);
+
+        // Act
+        services.AddA2AServer(AgentName);
+
+        // Assert
+        await using var provider = services.BuildServiceProvider();
+        var server = provider.GetKeyedService<A2AServer>(AgentName);
+        Assert.NotNull(server);
+    }
+
+    /// <summary>
+    /// Verifies that when a custom AgentSessionStore is registered, AddA2AServer uses it
+    /// instead of the default InMemoryAgentSessionStore.
+    /// </summary>
+    [Fact]
+    public async Task AddA2AServer_WithCustomAgentSessionStore_ResolvesSuccessfullyAsync()
+    {
+        // Arrange
+        const string AgentName = "custom-sessionstore-agent";
+        var services = new ServiceCollection();
+        services.AddKeyedSingleton(AgentName, (_, _) => CreateAgentMock(AgentName).Object);
+
+        var mockSessionStore = new Mock<AgentSessionStore>();
+        services.AddKeyedSingleton(AgentName, mockSessionStore.Object);
+
+        // Act
+        services.AddA2AServer(AgentName);
+
+        // Assert
+        await using var provider = services.BuildServiceProvider();
+        var server = provider.GetKeyedService<A2AServer>(AgentName);
+        Assert.NotNull(server);
+    }
+
+    /// <summary>
+    /// Verifies that when a custom IAgentHandler is registered, AddA2AServer uses it
+    /// instead of creating a default A2AAgentHandler.
+    /// </summary>
+    [Fact]
+    public async Task AddA2AServer_WithCustomAgentHandler_ResolvesSuccessfullyAsync()
+    {
+        // Arrange
+        const string AgentName = "custom-handler-agent";
+        var services = new ServiceCollection();
+        services.AddKeyedSingleton(AgentName, (_, _) => CreateAgentMock(AgentName).Object);
+
+        var mockHandler = new Mock<IAgentHandler>();
+        services.AddKeyedSingleton(AgentName, mockHandler.Object);
+
+        // Act
+        services.AddA2AServer(AgentName);
+
+        // Assert
+        await using var provider = services.BuildServiceProvider();
+        var server = provider.GetKeyedService<A2AServer>(AgentName);
+        Assert.NotNull(server);
+    }
+
+    /// <summary>
+    /// Verifies that the configureOptions callback is invoked when provided.
+    /// </summary>
+    [Fact]
+    public async Task AddA2AServer_WithConfigureOptions_InvokesCallbackAsync()
+    {
+        // Arrange
+        const string AgentName = "options-agent";
+        var services = new ServiceCollection();
+        services.AddKeyedSingleton(AgentName, (_, _) => CreateAgentMock(AgentName).Object);
+
+        bool callbackInvoked = false;
+
+        // Act
+        services.AddA2AServer(AgentName, options =>
+        {
+            callbackInvoked = true;
+            options.AgentRunMode = AgentRunMode.AllowBackgroundIfSupported;
+        });
+
+        // Assert - callback is invoked during resolution
+        await using var provider = services.BuildServiceProvider();
+        var server = provider.GetKeyedService<A2AServer>(AgentName);
+        Assert.NotNull(server);
+        Assert.True(callbackInvoked);
+    }
+
+    /// <summary>
+    /// Verifies that AddA2AServer with a null configureOptions does not throw.
+    /// </summary>
+    [Fact]
+    public async Task AddA2AServer_WithNullConfigureOptions_ResolvesSuccessfullyAsync()
+    {
+        // Arrange
+        const string AgentName = "null-options-agent";
+        var services = new ServiceCollection();
+        services.AddKeyedSingleton(AgentName, (_, _) => CreateAgentMock(AgentName).Object);
+
+        // Act
+        services.AddA2AServer(AgentName, configureOptions: null);
+
+        // Assert
+        await using var provider = services.BuildServiceProvider();
+        var server = provider.GetKeyedService<A2AServer>(AgentName);
+        Assert.NotNull(server);
+    }
+
+    /// <summary>
+    /// Verifies that AddA2AServer throws when the agent name is null.
+    /// </summary>
+    [Fact]
+    public void AddA2AServer_WithNullAgentName_ThrowsArgumentException()
+    {
+        // Arrange
+        var services = new ServiceCollection();
+
+        // Act & Assert
+        Assert.ThrowsAny<ArgumentException>(() => services.AddA2AServer(agentName: null!));
+    }
+
+    /// <summary>
+    /// Verifies that AddA2AServer throws when the agent name is whitespace.
+    /// </summary>
+    [Fact]
+    public void AddA2AServer_WithWhitespaceAgentName_ThrowsArgumentException()
+    {
+        // Arrange
+        var services = new ServiceCollection();
+
+        // Act & Assert
+        Assert.ThrowsAny<ArgumentException>(() => services.AddA2AServer(agentName: "  "));
+    }
+
+    /// <summary>
+    /// Verifies that AddA2AServer throws when the services parameter is null.
+    /// </summary>
+    [Fact]
+    public void AddA2AServer_WithNullServices_ThrowsArgumentNullException()
+    {
+        // Arrange
+        IServiceCollection services = null!;
+
+        // Act & Assert
+        Assert.Throws<ArgumentNullException>(() => services.AddA2AServer("agent"));
+    }
+
+    /// <summary>
+    /// Verifies that AddA2AServer with an agent instance throws when the agent is null.
+    /// </summary>
+    [Fact]
+    public void AddA2AServer_WithNullAgent_ThrowsArgumentNullException()
+    {
+        // Arrange
+        var services = new ServiceCollection();
+
+        // Act & Assert
+        Assert.Throws<ArgumentNullException>(() => services.AddA2AServer(agent: null!));
+    }
+
+    private static Mock<AIAgent> CreateAgentMock(string name)
+    {
+        Mock<AIAgent> agentMock = new() { CallBase = true };
+        agentMock.SetupGet(x => x.Name).Returns(name);
+        agentMock
+            .Protected()
+            .Setup<ValueTask<AgentSession>>("CreateSessionCoreAsync", ItExpr.IsAny<CancellationToken>())
+            .ReturnsAsync(new TestAgentSession());
+        agentMock
+            .Protected()
+            .Setup<Task<AgentResponse>>("RunCoreAsync",
+                ItExpr.IsAny<IEnumerable<ChatMessage>>(),
+                ItExpr.IsAny<AgentSession?>(),
+                ItExpr.IsAny<AgentRunOptions?>(),
+                ItExpr.IsAny<CancellationToken>())
+            .ReturnsAsync(new AgentResponse([new ChatMessage(ChatRole.Assistant, "Test response")]));
+
+        return agentMock;
+    }
+
+    private sealed class TestAgentSession : AgentSession;
+}

dotnet/tests/Microsoft.Agents.AI.Hosting.A2A.UnitTests/AgentRunModeTests.cs

@@ -130,16 +130,32 @@ public sealed class AgentRunModeTests
     }
 
     /// <summary>
-    /// Verifies that two AllowBackgroundWhen instances with different delegates are considered equal,
-    /// because equality is based on the mode value ("dynamic"), not the delegate.
+    /// Verifies that two AllowBackgroundWhen instances with different delegates are not considered equal,
+    /// because equality includes delegate identity for dynamic modes.
     /// </summary>
     [Fact]
-    public void Equals_AllowBackgroundWhen_DifferentDelegates_AreEqual()
+    public void Equals_AllowBackgroundWhen_DifferentDelegates_AreNotEqual()
     {
         // Arrange
         var mode1 = AgentRunMode.AllowBackgroundWhen((_, _) => ValueTask.FromResult(true));
         var mode2 = AgentRunMode.AllowBackgroundWhen((_, _) => ValueTask.FromResult(false));
 
+        // Act & Assert
+        Assert.False(mode1.Equals(mode2));
+        Assert.True(mode1 != mode2);
+    }
+
+    /// <summary>
+    /// Verifies that two AllowBackgroundWhen instances with the same delegate are considered equal.
+    /// </summary>
+    [Fact]
+    public void Equals_AllowBackgroundWhen_SameDelegate_AreEqual()
+    {
+        // Arrange
+        Func<A2ARunDecisionContext, CancellationToken, ValueTask<bool>> callback = (_, _) => ValueTask.FromResult(true);
+        var mode1 = AgentRunMode.AllowBackgroundWhen(callback);
+        var mode2 = AgentRunMode.AllowBackgroundWhen(callback);
+
         // Act & Assert
         Assert.True(mode1.Equals(mode2));
         Assert.True(mode1 == mode2);