Enable MCP Task support for long-running .NET operations (build, test, publish)

DotNetMcp.Tests/DotNetMcp.Tests.csproj

@@ -6,6 +6,8 @@
     <Nullable>enable</Nullable>
     <IsPackable>false</IsPackable>
     <OutputType>Exe</OutputType>
+    <!-- MCPEXP001: Task-related APIs (IMcpTaskStore, ToolTaskSupport, McpTasksCapability) are experimental in the MCP SDK -->
+    <NoWarn>$(NoWarn);MCPEXP001</NoWarn>
   </PropertyGroup>
 
   <ItemGroup>

DotNetMcp.Tests/Server/McpConformanceTests.cs

@@ -520,6 +520,65 @@ public async Task Server_ResourceList_ShouldHaveValidStructure()
 
     #endregion
 
+    #region MCP Task Support Tests
+
+    [Fact]
+    public void Server_ShouldAdvertiseTasksCapability()
+    {
+        // Arrange
+        Assert.NotNull(_client);
+
+        // Assert - server should expose tasks capability (InMemoryMcpTaskStore is registered)
+        Assert.NotNull(_client.ServerCapabilities);
+        Assert.NotNull(_client.ServerCapabilities.Tasks);
+    }
+
+    [Fact]
+    public void Server_TasksCapability_ShouldSupportListAndCancel()
+    {
+        // Arrange
+        Assert.NotNull(_client);
+
+        // Assert
+        var tasks = _client.ServerCapabilities?.Tasks;
+        Assert.NotNull(tasks);
+        Assert.NotNull(tasks.List);
+        Assert.NotNull(tasks.Cancel);
+    }
+
+    [Fact]
+    public async Task Server_DotnetProject_ShouldHaveTaskSupport()
+    {
+        // Arrange
+        Assert.NotNull(_client);
+
+        // Act
+        var tools = await _client.ListToolsAsync(cancellationToken: TestContext.Current.CancellationToken);
+        var projectTool = tools.FirstOrDefault(t => t.Name == "dotnet_project");
+
+        // Assert - dotnet_project should declare TaskSupport = Optional so clients can run
+        // long operations (build, test, publish) as async tasks
+        Assert.NotNull(projectTool);
+        var execution = projectTool.ProtocolTool.Execution;
+        Assert.NotNull(execution);
+        Assert.Equal(ModelContextProtocol.Protocol.ToolTaskSupport.Optional, execution.TaskSupport);
+    }
+
+    [Fact]
+    public async Task Server_TaskList_ShouldReturnEmptyWhenNoTasksRunning()
+    {
+        // Arrange
+        Assert.NotNull(_client);
+
+        // Act
+        var tasks = await _client.ListTasksAsync(cancellationToken: TestContext.Current.CancellationToken);
+
+        // Assert - no tasks should be running at server start
+        Assert.NotNull(tasks);
+    }
+
+    #endregion
+
     #region Helper Methods
 
     /// <summary>

DotNetMcp.Tests/Server/ServerCapabilitiesTests.cs

@@ -209,6 +209,21 @@ public async Task DotnetServerCapabilities_SdkVersions_Lts_IsNet100()
         Assert.Equal("net10.0", lts);
     }
 
+    [Fact]
+    public async Task DotnetServerCapabilities_Supports_AsyncTasks_IsTrue()
+    {
+        // Act
+        var result = (await _tools.DotnetServerCapabilities()).GetText();
+        var jsonDoc = JsonDocument.Parse(result);
+        var asyncTasks = jsonDoc.RootElement
+            .GetProperty("supports")
+            .GetProperty("asyncTasks")
+            .GetBoolean();
+
+        // Assert - MCP Task support is enabled via InMemoryMcpTaskStore
+        Assert.True(asyncTasks);
+    }
+
     [Fact]
     public async Task DotnetServerCapabilities_JsonSchema_MatchesExpectedStructure()
     {
@@ -232,6 +247,7 @@ public async Task DotnetServerCapabilities_JsonSchema_MatchesExpectedStructure()
         Assert.True(capabilities.Supports.MachineReadable);
         Assert.True(capabilities.Supports.Cancellation);
         Assert.True(capabilities.Supports.Telemetry);
+        Assert.True(capabilities.Supports.AsyncTasks);
         Assert.NotNull(capabilities.SdkVersions);
         Assert.NotEmpty(capabilities.SdkVersions.Installed);
         Assert.Equal("net10.0", capabilities.SdkVersions.Recommended);

DotNetMcp/DotNetMcp.csproj

@@ -9,7 +9,8 @@
     <!-- Suppress CS1591 for missing XML comments on non-tool classes -->
     <!-- The source generator creates [Description] attributes from XML documentation for MCP tool methods -->
     <!-- CS1066 is now automatically suppressed by the SDK for MCP server methods -->
-    <NoWarn>$(NoWarn);CS1591</NoWarn>
+    <!-- MCPEXP001: IMcpTaskStore and related task APIs are experimental in the MCP SDK -->
+    <NoWarn>$(NoWarn);CS1591;MCPEXP001</NoWarn>
 
     <!-- NuGet Package Metadata -->
     <PackageId>Community.Mcp.DotNet</PackageId>

DotNetMcp/Program.cs

@@ -2,6 +2,7 @@
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
+using ModelContextProtocol;
 using ModelContextProtocol.Protocol;
 
 var builder = Host.CreateApplicationBuilder(args);
@@ -17,6 +18,10 @@
 // Register ProcessSessionManager as a singleton
 builder.Services.AddSingleton<ProcessSessionManager>();
 
+// Register InMemoryMcpTaskStore to enable MCP Task support for long-running operations.
+// This allows AI clients to run build/test/publish as async tasks with polling and cancellation.
+builder.Services.AddSingleton<IMcpTaskStore, InMemoryMcpTaskStore>();
+
 builder.Services.AddMcpServer(options =>
 {
     // Configure server implementation with .NET-themed icon

DotNetMcp/Server/ServerCapabilities.cs

@@ -69,6 +69,14 @@ public sealed class ServerFeatureSupport
     /// </summary>
     [JsonPropertyName("telemetry")]
     public bool Telemetry { get; init; }
+
+    /// <summary>
+    /// Whether the server supports MCP Task augmentation for long-running operations such as
+    /// build, test, and publish. When true, AI clients can call supported tools as async tasks
+    /// and poll for completion instead of blocking on the result.
+    /// </summary>
+    [JsonPropertyName("asyncTasks")]
+    public bool AsyncTasks { get; init; }
 }
 
 /// <summary>

DotNetMcp/Tools/Cli/DotNetCliTools.Misc.cs

@@ -68,7 +68,8 @@ public async partial Task<CallToolResult> DotnetServerCapabilities()
                 StructuredErrors = true,
                 MachineReadable = true,
                 Cancellation = true,
-                Telemetry = true  // SDK v0.6+ supports request duration logging and OpenTelemetry semantic conventions
+                Telemetry = true,  // SDK v0.6+ supports request duration logging and OpenTelemetry semantic conventions
+                AsyncTasks = true  // MCP Task support enabled: long-running operations (build, test, publish) can run as async tasks
             },
             SdkVersions = new SdkVersionInfo
             {

DotNetMcp/Tools/Cli/DotNetCliTools.Project.Consolidated.cs

@@ -55,7 +55,7 @@
     /// <param name="propertyValue">Value to set for SetProperty action (e.g., 'Exe')</param>
     /// <param name="itemType">Item type for AddItem/RemoveItem/ListItems actions (e.g., 'Using', 'Content', 'None')</param>
     /// <param name="include">The Include attribute value for AddItem/RemoveItem actions</param>
-    [McpServerTool(Title = ".NET Project", Destructive = true, IconSource = "https://raw.githubusercontent.com/microsoft/fluentui-emoji/62ecdc0d7ca5c6df32148c169556bc8d3782fca4/assets/File%20Folder/Flat/file_folder_flat.svg")]
+    [McpServerTool(Title = ".NET Project", Destructive = true, TaskSupport = ToolTaskSupport.Optional, IconSource = "https://raw.githubusercontent.com/microsoft/fluentui-emoji/62ecdc0d7ca5c6df32148c169556bc8d3782fca4/assets/File%20Folder/Flat/file_folder_flat.svg")]
     [McpMeta("category", "project")]
     [McpMeta("priority", 10.0)]
     [McpMeta("commonlyUsed", true)]
@@ -916,7 +916,7 @@
 
         // Determine project argument style based on effective runner
         bool usePositionalArg = effectiveRunner == TestRunner.VSTest;
         string projectArgumentStyle;
 
         if (!string.IsNullOrEmpty(project))
         {