microsoft · rido-min · Jan 27, 2026 · Jan 22, 2026 · Jan 22, 2026 · Jan 22, 2026
diff --git a/.azdo/ci.yaml b/.azdo/ci.yaml
@@ -19,10 +19,16 @@ stages:
     steps:
 
       - task: UseDotNet@2
-        displayName: 'Use .NET 9'
+        displayName: 'Use .NET 8'
         inputs:
           packageType: 'sdk'
-          version: '9.0.x'
+          version: '8.0.x'
+
+      - task: UseDotNet@2
+        displayName: 'Use .NET 10'
+        inputs:
+          packageType: 'sdk'
+          version: '10.0.x'
 
       - script: dotnet restore 
         displayName: 'Restore'

diff --git a/Libraries/Microsoft.Teams.Apps/Annotations/TeamsControllerAttribute.cs b/Libraries/Microsoft.Teams.Apps/Annotations/TeamsControllerAttribute.cs
@@ -4,6 +4,7 @@
 namespace Microsoft.Teams.Apps.Annotations;
 
 [AttributeUsage(AttributeTargets.Class, Inherited = true)]
+[Obsolete("Use Minimal APIs instead.")]
 public class TeamsControllerAttribute(string? name = null) : Attribute
 {
     public string? Name { get; } = name;

diff --git a/Libraries/Microsoft.Teams.Apps/AppRouting.cs b/Libraries/Microsoft.Teams.Apps/AppRouting.cs
@@ -19,6 +19,7 @@ public partial class App
 {
     internal IRouter Router { get; } = new Router();
 
+    [Obsolete("Use Minimal APIs instead.")]
     public App AddController<T>(T controller) where T : class
     {
         var type = controller.GetType();

diff --git a/...ms.Plugins/Microsoft.Teams.Plugins.AspNetCore.BotBuilder/Controllers/MessageController.cs b/...ms.Plugins/Microsoft.Teams.Plugins.AspNetCore.BotBuilder/Controllers/MessageController.cs
@@ -10,6 +10,7 @@
 namespace Microsoft.Teams.Plugins.AspNetCore.BotBuilder
 {
     [ApiController]
+    [Obsolete("Use Minimal APIs instead.")]
     public class MessageController : ControllerBase
     {
         private readonly IBotFrameworkHttpAdapter _adapter;

diff --git a/...lugins/Microsoft.Teams.Plugins.AspNetCore.BotBuilder/Extensions/HostApplicationBuilder.cs b/...lugins/Microsoft.Teams.Plugins.AspNetCore.BotBuilder/Extensions/HostApplicationBuilder.cs
@@ -1,25 +1,18 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
-using Microsoft.AspNetCore.Mvc.ApplicationParts;
 using Microsoft.Bot.Builder;
 using Microsoft.Bot.Builder.Integration.AspNet.Core;
 using Microsoft.Bot.Connector.Authentication;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
-using Microsoft.Teams.Plugins.AspNetCore.Controllers;
 
 namespace Microsoft.Teams.Plugins.AspNetCore.Extensions;
 
 public static class HostApplicationBuilderExtensions
 {
     public static IHostApplicationBuilder AddBotBuilder(this IHostApplicationBuilder builder)
     {
-        builder.Services.AddControllers().ConfigureApplicationPartManager((apm) =>
-        {
-            apm.FeatureProviders.Add(new RemoveDefaultMessageController());
-            apm.ApplicationParts.Add(new AssemblyPart(typeof(MessageController).Assembly));
-        });
         return builder;
     }
 
@@ -28,11 +21,7 @@ public static IHostApplicationBuilder AddBotBuilder<TBot>(this IHostApplicationB
         builder.Services.AddSingleton(authentication);
         builder.Services.AddSingleton(adapter);
         builder.Services.AddTransient<IBot, TBot>();
-        builder.Services.AddControllers().ConfigureApplicationPartManager((apm) =>
-        {
-            apm.FeatureProviders.Add(new RemoveDefaultMessageController());
-            apm.ApplicationParts.Add(new AssemblyPart(typeof(MessageController).Assembly));
-        });
+
         return builder;
     }
 
@@ -41,11 +30,7 @@ public static IHostApplicationBuilder AddBotBuilder<TBot, TBotFrameworkHttpAdapt
         builder.Services.AddSingleton<BotFrameworkAuthentication, TBotFrameworkAuthentication>();
         builder.Services.AddSingleton<IBotFrameworkHttpAdapter, TBotFrameworkHttpAdapter>();
         builder.Services.AddTransient<IBot, TBot>();
-        builder.Services.AddControllers().ConfigureApplicationPartManager((apm) =>
-        {
-            apm.FeatureProviders.Add(new RemoveDefaultMessageController());
-            apm.ApplicationParts.Add(new AssemblyPart(typeof(MessageController).Assembly));
-        });
+
         return builder;
     }
 }
diff --git a/...s.Plugins/Microsoft.Teams.Plugins.AspNetCore.BotBuilder/RemoveDefaultMessageController.cs b/...s.Plugins/Microsoft.Teams.Plugins.AspNetCore.BotBuilder/RemoveDefaultMessageController.cs
diff --git a/...ams.Plugins/Microsoft.Teams.Plugins.AspNetCore.DevTools/Controllers/ActivityController.cs b/...ams.Plugins/Microsoft.Teams.Plugins.AspNetCore.DevTools/Controllers/ActivityController.cs
@@ -16,6 +16,7 @@
 namespace Microsoft.Teams.Plugins.AspNetCore.DevTools.Controllers;
 
 [ApiController]
+[Obsolete("Use Minimal APIs instead.")]
 public class ActivityController : ControllerBase
 {
     private readonly DevToolsPlugin _plugin;

diff --git a/...crosoft.Teams.Plugins/Microsoft.Teams.Plugins.AspNetCore/Controllers/MessageController.cs b/...crosoft.Teams.Plugins/Microsoft.Teams.Plugins.AspNetCore/Controllers/MessageController.cs
diff --git a/...crosoft.Teams.Plugins/Microsoft.Teams.Plugins.AspNetCore/Extensions/ApplicationBuilder.cs b/...crosoft.Teams.Plugins/Microsoft.Teams.Plugins.AspNetCore/Extensions/ApplicationBuilder.cs
@@ -4,11 +4,15 @@
 using System.Reflection;
 
 using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Http;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Teams.Api.Auth;
 using Microsoft.Teams.Apps;
 using Microsoft.Teams.Apps.Annotations;
 using Microsoft.Teams.Apps.Plugins;
 
+using static Microsoft.Teams.Plugins.AspNetCore.Extensions.HostApplicationBuilderExtensions;
+
 namespace Microsoft.Teams.Plugins.AspNetCore.Extensions;
 
 public static partial class ApplicationBuilderExtensions
@@ -28,7 +32,9 @@ public static App UseTeams(this IApplicationBuilder builder, bool routing = true
 
         foreach (var type in types)
         {
+#pragma warning disable CS0618 // Type or member is obsolete
             var attribute = type.GetCustomAttribute<TeamsControllerAttribute>();
+#pragma warning restore CS0618 // Type or member is obsolete
 
             if (attribute is null)
             {
@@ -39,7 +45,9 @@ public static App UseTeams(this IApplicationBuilder builder, bool routing = true
 
             if (controller is not null)
             {
+#pragma warning disable CS0618 // Type or member is obsolete
                 app.AddController(controller);
+#pragma warning restore CS0618 // Type or member is obsolete
             }
         }
 
@@ -57,7 +65,24 @@ public static App UseTeams(this IApplicationBuilder builder, bool routing = true
         {
             builder.UseRouting();
             builder.UseAuthorization();
-            builder.UseEndpoints(endpoints => endpoints.MapControllers());
+
+            // Get AspNetCorePlugin for endpoint registration
+            var aspNetCorePlugin = plugins.OfType<AspNetCorePlugin>().FirstOrDefault();
+
+            builder.UseEndpoints(endpoints =>
+            {
+                // Map AspNetCorePlugin endpoint
+                if (aspNetCorePlugin is not null)
+                {
+                    endpoints.MapPost("/api/messages", async (HttpContext httpContext, CancellationToken cancellationToken) =>
+                    {
+                        return await aspNetCorePlugin.Do(httpContext, cancellationToken);
+                    }).RequireAuthorization(TeamsTokenAuthConstants.AuthorizationPolicy);
+                }
+
+                // Map controller endpoints (obsolete)
+                endpoints.MapControllers();
+            });
         }
 
         return app;

diff --git a/Microsoft.Teams.sln b/Microsoft.Teams.sln
@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio Version 17
-VisualStudioVersion = 17.0.31903.59
+# Visual Studio Version 18
+VisualStudioVersion = 18.2.11415.280 d18.0
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Libraries", "Libraries", "{809F86A1-1C4C-B159-0CD4-DF9D33D876CE}"
 EndProject
@@ -85,6 +85,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Samples.AI", "Samples\Sampl
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Samples.Meetings", "Samples\Samples.Meetings\Samples.Meetings.csproj", "{FCEEF7AD-1E78-4615-8BE4-7B46B034A514}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Deprecated.Controllers", "Samples\Deprecated.Controllers\Deprecated.Controllers.csproj", "{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -515,6 +517,18 @@ Global
 		{FCEEF7AD-1E78-4615-8BE4-7B46B034A514}.Release|x64.Build.0 = Release|Any CPU
 		{FCEEF7AD-1E78-4615-8BE4-7B46B034A514}.Release|x86.ActiveCfg = Release|Any CPU
 		{FCEEF7AD-1E78-4615-8BE4-7B46B034A514}.Release|x86.Build.0 = Release|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Debug|x64.Build.0 = Debug|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Debug|x86.Build.0 = Debug|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Release|Any CPU.Build.0 = Release|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Release|x64.ActiveCfg = Release|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Release|x64.Build.0 = Release|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Release|x86.ActiveCfg = Release|Any CPU
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -558,6 +572,7 @@ Global
 		{783599E3-9841-4377-9590-4A5D9EC0023D} = {0AB3BF05-4346-4AA6-1389-037BE0695223}
 		{BCD1AE81-8D5D-461F-AB63-7C0E5882F89B} = {5D20AA90-6969-D8BD-9DCD-8634F4692FDA}
 		{FCEEF7AD-1E78-4615-8BE4-7B46B034A514} = {5D20AA90-6969-D8BD-9DCD-8634F4692FDA}
+		{1F0A8B29-3792-4E11-B6A7-43F03F9A591F} = {5D20AA90-6969-D8BD-9DCD-8634F4692FDA}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {378263F2-C2B2-4DB1-83CF-CA228AF03ABF}

diff --git a/Samples/Deprecated.Controllers/Deprecated.Controllers.csproj b/Samples/Deprecated.Controllers/Deprecated.Controllers.csproj
@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="10.0.2" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\Libraries\Microsoft.Teams.Plugins\Microsoft.Teams.Plugins.AspNetCore.DevTools\Microsoft.Teams.Plugins.AspNetCore.DevTools.csproj" />
+    <ProjectReference Include="..\..\Libraries\Microsoft.Teams.Plugins\Microsoft.Teams.Plugins.AspNetCore\Microsoft.Teams.Plugins.AspNetCore.csproj" />
+  </ItemGroup>
+
+</Project>
diff --git a/Samples/Deprecated.Controllers/MainController.cs b/Samples/Deprecated.Controllers/MainController.cs
@@ -0,0 +1,17 @@
+using Microsoft.Teams.Api.Activities;
+using Microsoft.Teams.Apps;
+using Microsoft.Teams.Apps.Annotations;
+using Microsoft.Teams.Apps.Activities;
+
+namespace Deprecated.Controllers;
+
+[TeamsController("main")]
+[Obsolete]
+public class MainController
+{
+    [Message]
+    public async Task OnMessage([Context] MessageActivity activity, [Context] IContext.Client client)
+    {
+        await client.Send($"you said \"{activity.Text}\"");
+    }
+}
diff --git a/Samples/Deprecated.Controllers/Program.cs b/Samples/Deprecated.Controllers/Program.cs
@@ -0,0 +1,20 @@
+using Microsoft.Teams.Plugins.AspNetCore.DevTools.Extensions;
+using Microsoft.Teams.Plugins.AspNetCore.Extensions;
+
+using Deprecated.Controllers;
+
+var builder = WebApplication.CreateBuilder(args);
+builder.AddTeams().AddTeamsDevTools();
+#pragma warning disable CS0612 // Type or member is obsolete
+builder.Services.AddTransient<MainController>();
+#pragma warning restore CS0612 // Type or member is obsolete
+
+var app = builder.Build();
+
+if (app.Environment.IsDevelopment())
+{
+    app.MapOpenApi();
+}
+
+app.UseTeams();
+app.Run();
diff --git a/Samples/Deprecated.Controllers/Properties/launchSettings.json b/Samples/Deprecated.Controllers/Properties/launchSettings.json
@@ -0,0 +1,15 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "applicationUrl": "http://localhost:3978",
+      "launchUrl": "devtools",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Local"
+      }
+    }
+  }
+}
diff --git a/Samples/Deprecated.Controllers/appsettings.Development.json b/Samples/Deprecated.Controllers/appsettings.Development.json
@@ -0,0 +1,12 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    },
+    "Microsoft.Teams": {
+      "Level": "info"
+    }
+  },
+  "AllowedHosts": "*"
+}
diff --git a/Samples/Deprecated.Controllers/appsettings.json b/Samples/Deprecated.Controllers/appsettings.json
@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}
diff --git a/Samples/Samples.Echo/Program.cs b/Samples/Samples.Echo/Program.cs
@@ -1,9 +1,10 @@
 using Microsoft.Teams.Apps.Activities;
 using Microsoft.Teams.Apps.Extensions;
+using Microsoft.Teams.Plugins.AspNetCore.DevTools.Extensions;
 using Microsoft.Teams.Plugins.AspNetCore.Extensions;
 
 var builder = WebApplication.CreateBuilder(args);
-builder.AddTeams();
+builder.AddTeams().AddTeamsDevTools();
 var app = builder.Build();
 var teams = app.UseTeams();
 

diff --git a/Samples/Samples.McpClient/Controller.cs b/Samples/Samples.McpClient/Controller.cs
@@ -6,6 +6,7 @@
 
 namespace Samples.McpClient;
 
+[Obsolete]
 [TeamsController]
 public class Controller(Func<OpenAIChatPrompt> _promptFactory)
 {

diff --git a/Samples/Samples.McpClient/Program.cs b/Samples/Samples.McpClient/Program.cs
@@ -7,7 +7,9 @@
 using Samples.McpClient;
 
 var builder = WebApplication.CreateBuilder(args);
+#pragma warning disable CS0612 // Type or member is obsolete
 builder.Services.AddTransient<Controller>().AddHttpContextAccessor();
+#pragma warning restore CS0612 // Type or member is obsolete
 builder.Services.AddSingleton((sp) => new McpClientPlugin().UseMcpServer("https://learn.microsoft.com/api/mcp"));
 builder.AddTeams().AddTeamsDevTools().AddOpenAI<DocsPrompt>();