Create a project template for an MCP server

src/ProjectTemplates/GeneratedContent.targets

@@ -10,6 +10,7 @@
     <_LocalChatTemplateVariant>aspire</_LocalChatTemplateVariant>
 
     <_ChatWithCustomDataContentRoot>$(MSBuildThisFileDirectory)Microsoft.Extensions.AI.Templates\src\ChatWithCustomData\</_ChatWithCustomDataContentRoot>
+    <_McpServerContentRoot>$(MSBuildThisFileDirectory)Microsoft.Extensions.AI.Templates\src\McpServer\</_McpServerContentRoot>
   </PropertyGroup>
 
   <Target Name="ComputeGeneratedContentProperties">
@@ -34,9 +35,11 @@
       <TemplatePackageVersion_AzureIdentity>1.14.0</TemplatePackageVersion_AzureIdentity>
       <TemplatePackageVersion_AzureSearchDocuments>11.6.0</TemplatePackageVersion_AzureSearchDocuments>
       <TemplatePackageVersion_CommunityToolkitAspire>9.4.1-beta.291</TemplatePackageVersion_CommunityToolkitAspire>
+      <TemplatePackageVersion_MicrosoftExtensionsHosting>10.0.0-preview.5.25277.114</TemplatePackageVersion_MicrosoftExtensionsHosting>
       <TemplatePackageVersion_MicrosoftExtensionsServiceDiscovery>9.3.0</TemplatePackageVersion_MicrosoftExtensionsServiceDiscovery>
       <TemplatePackageVersion_MicrosoftSemanticKernel>1.53.0</TemplatePackageVersion_MicrosoftSemanticKernel>
       <TemplatePackageVersion_MicrosoftSemanticKernel_Preview>1.53.0-preview</TemplatePackageVersion_MicrosoftSemanticKernel_Preview>
+      <TemplatePackageVersion_ModelContextProtocol>0.3.0-preview.1</TemplatePackageVersion_ModelContextProtocol>
       <TemplatePackageVersion_OllamaSharp>5.1.18</TemplatePackageVersion_OllamaSharp>
       <TemplatePackageVersion_OpenTelemetry>1.12.0</TemplatePackageVersion_OpenTelemetry>
       <TemplatePackageVersion_PdfPig>0.1.10</TemplatePackageVersion_PdfPig>
@@ -64,9 +67,11 @@
         TemplatePackageVersion_AzureIdentity=$(TemplatePackageVersion_AzureIdentity);
         TemplatePackageVersion_AzureSearchDocuments=$(TemplatePackageVersion_AzureSearchDocuments);
         TemplatePackageVersion_CommunityToolkitAspire=$(TemplatePackageVersion_CommunityToolkitAspire);
+        TemplatePackageVersion_MicrosoftExtensionsHosting=$(TemplatePackageVersion_MicrosoftExtensionsHosting);
         TemplatePackageVersion_MicrosoftExtensionsServiceDiscovery=$(TemplatePackageVersion_MicrosoftExtensionsServiceDiscovery);
         TemplatePackageVersion_MicrosoftSemanticKernel=$(TemplatePackageVersion_MicrosoftSemanticKernel);
         TemplatePackageVersion_MicrosoftSemanticKernel_Preview=$(TemplatePackageVersion_MicrosoftSemanticKernel_Preview);
+        TemplatePackageVersion_ModelContextProtocol=$(TemplatePackageVersion_ModelContextProtocol);
         TemplatePackageVersion_OllamaSharp=$(TemplatePackageVersion_OllamaSharp);
         TemplatePackageVersion_OpenTelemetry=$(TemplatePackageVersion_OpenTelemetry);
         TemplatePackageVersion_PdfPig=$(TemplatePackageVersion_PdfPig);
@@ -100,6 +105,9 @@
       <GeneratedContent
         Include="$(_ChatWithCustomDataContentRoot)ChatWithCustomData-CSharp.ServiceDefaults\ChatWithCustomData-CSharp.ServiceDefaults.csproj.in"
         OutputPath="$(_ChatWithCustomDataContentRoot)ChatWithCustomData-CSharp.ServiceDefaults\ChatWithCustomData-CSharp.ServiceDefaults.csproj" />
+      <GeneratedContent
+        Include="$(_McpServerContentRoot)McpServer-CSharp\McpServer-CSharp.csproj.in"
+        OutputPath="$(_McpServerContentRoot)McpServer-CSharp\McpServer-CSharp.csproj" />
 
       <!-- The following content only gets generated when using just-built packages -->
       <_GeneratedContentEnablingJustBuiltPackages

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/Microsoft.Extensions.AI.Templates.csproj

@@ -61,6 +61,16 @@
         **\NuGet.config;
         **\Directory.Build.targets;
         **\Directory.Build.props;" />
+
+    <!-- Keep the exclude patterns below in sync with those in McpServerSnapshotTests.cs -->
+    <Content
+      Include="src\McpServer\**\*"
+      Exclude="
+        **\bin\**;
+        **\obj\**;
+        **\.vs\**;
+        **\*.sln;
+        **\*.in;" />
     <None Include="THIRD-PARTY-NOTICES.TXT" Pack="true" PackagePath="." />
     <Compile Remove="**\*" />
   </ItemGroup>

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/src/McpServer/McpServer-CSharp/.mcp/server.json

@@ -0,0 +1,20 @@
+{
+  "description": "<your description here>",
+  "name": "io.github.<your GitHub username here>/<your repo name>",
+  "packages": [
+    {
+      "registry_name": "nuget",
+      "name": "<your package ID here>",
+      "version": "0.1.0-beta",
+      "package_arguments": [],
+      "environment_variables": []
+    }
+  ],
+  "repository": {
+    "url": "https://github.com/<your GitHub username here>/<your repo name>",
+    "source": "github"
+  },
+  "version_detail": {
+    "version": "0.1.0-beta"
+  }
+}

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/src/McpServer/McpServer-CSharp/.template.config/dotnetcli.host.json

@@ -0,0 +1,7 @@
+{
+  "$schema": "https://json.schemastore.org/dotnetcli.host",
+  "symbolInfo": {},
+  "usageExamples": [
+    ""
+  ]
+}

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/src/McpServer/McpServer-CSharp/.template.config/ide.host.json

@@ -0,0 +1,6 @@
+{
+  "$schema": "https://json.schemastore.org/ide.host",
+  "order": 0,
+  "icon": "ide/icon.ico",
+  "symbolInfo": []
+}

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/src/McpServer/McpServer-CSharp/.template.config/template.json

@@ -0,0 +1,46 @@
+{
+  "$schema": "http://json.schemastore.org/template",
+  "author": "Microsoft",
+  "classifications": [
+    "Common",
+    "AI",
+    "MCP"
+  ],
+  "identity": "Microsoft.Extensions.AI.Templates.McpServer.CSharp",
+  "name": "Local MCP Server Console App",
+  "description": "A project template for creating a Model Context Protocol (MCP) server using C# and the ModelContextProtocol package.",
+  "shortName": "mcpserver",
+  "defaultName": "McpServer",
+  "sourceName": "McpServer-CSharp",
+  "preferNameDirectory": true,
+  "tags": {
+    "language": "C#",
+    "type": "project"
+  },
+  "symbols": {
+    "hostIdentifier": {
+      "type": "bind",
+      "binding": "HostIdentifier"
+    }
+  },
+  "primaryOutputs": [
+    {
+      "path": "./README.md"
+    },
+    {
+      "path": "./McpServer-CSharp.csproj"
+    }
+  ],
+  "postActions": [
+    {
+      "condition": "(hostIdentifier != \"dotnetcli\" && hostIdentifier != \"dotnetcli-preview\")",
+      "description": "Opens README file in the editor",
+      "manualInstructions": [],
+      "actionId": "84C0DA21-51C8-4541-9940-6CA19AF04EE6",
+      "args": {
+        "files": "0"
+      },
+      "continueOnError": true
+    }
+  ]
+}

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/src/McpServer/McpServer-CSharp/McpServer-CSharp.csproj.in

@@ -0,0 +1,32 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <OutputType>Exe</OutputType>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+
+    <!-- Set up the NuGet package to be an MCP server -->
+    <PackAsTool>true</PackAsTool>
+    <PackageType>McpServer</PackageType>
+
+    <!-- Set recommended package metadata -->
+    <PackageReadmeFile>README.md</PackageReadmeFile>
+    <PackageId>SampleMcpServer</PackageId>
+    <PackageVersion>0.1.0-beta</PackageVersion>
+    <PackageTags>AI; MCP; server; stdio</PackageTags>
+    <Description>An MCP server using the MCP C# SDK.</Description>
+  </PropertyGroup>
+
+  <!-- Include additional files for browsing the MCP server. -->
+  <ItemGroup>
+    <None Include=".mcp\server.json" Pack="true" PackagePath="/.mcp/" />
+    <None Include="README.md" Pack="true" PackagePath="/" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Hosting" Version="${TemplatePackageVersion_MicrosoftExtensionsHosting}" />
+    <PackageReference Include="ModelContextProtocol" Version="${TemplatePackageVersion_ModelContextProtocol}" />
+  </ItemGroup>
+
+</Project>

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/src/McpServer/McpServer-CSharp/Program.cs

@@ -0,0 +1,16 @@
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+
+var builder = Host.CreateApplicationBuilder(args);
+
+// Configure all logs to go to stderr (stdout is used for the MCP protocol messages).
+builder.Logging.AddConsole(o => o.LogToStandardErrorThreshold = LogLevel.Trace);
+
+// Add the MCP services: the transport to use (stdio) and the tools to register.
+builder.Services
+    .AddMcpServer()
+    .WithStdioServerTransport()
+    .WithTools<RandomNumberTools>();
+
+await builder.Build().RunAsync();

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/src/McpServer/McpServer-CSharp/README.md

@@ -0,0 +1,80 @@
+# MCP Server
+
+This README was created using the C# MCP server template project. It demonstrates how you can easily create an MCP server using C# and then package it in a NuGet package.
+
+See [aka.ms/nuget/mcp/guide](https://aka.ms/nuget/mcp/guide) for the full guide.
+
+## Checklist before publishing to NuGet.org
+
+- Test the MCP server locally using the steps below.
+- Update the package metadata in the .csproj file, in particular the `<PackageId>`.
+- Update `.mcp/server.json` to declare your MCP server's inputs.
+  - See [configuring inputs](https://aka.ms/nuget/mcp/guide/configuring-inputs) for more details.
+- Pack the project using `dotnet pack`.
+
+The `bin/Release` directory will contain the package file (.nupkg), which can be [published to NuGet.org](https://learn.microsoft.com/nuget/nuget-org/publish-a-package).
+
+## Using the MCP Server in VS Code
+
+Once the MCP server package is published to NuGet.org, you can use the following VS Code user configuration to download and install the MCP server package. See [Use MCP servers in VS Code (Preview)](https://code.visualstudio.com/docs/copilot/chat/mcp-servers) for more information about using MCP servers in VS Code.
+
+```json
+{
+  "mcp": {
+    "servers": {
+      "McpServer-CSharp": {
+        "type": "stdio",
+        "command": "dotnet",
+        "args": [
+          "tool",
+          "exec",
+          "<your package ID here>",
+          "--version",
+          "<your package version here>",
+          "--yes"
+        ]
+      }
+    }
+  }
+}
+```
+
+Now you can ask Copilot Chat for a random number, for example, `Give me 3 random numbers`. It should prompt you to use the `get_random_number` tool on the `McpServer-CSharp` MCP server and show you the results.
+
+## Developing locally in VS Code
+
+To test this MCP server from source code (locally) without using a built MCP server package, create a `.vscode/mcp.json` file (a VS Code workspace settings file) in your project directory and add the following configuration:
+
+```json
+{
+  "servers": {
+    "McpServer-CSharp": {
+      "type": "stdio",
+      "command": "dotnet",
+      "args": [
+        "run"
+      ]
+    }
+  }
+}
+```
+
+Alternatively, you can configure your VS Code user settings to use your local project:
+
+```json
+{
+  "mcp": {
+    "servers": {
+      "McpServer-CSharp": {
+        "type": "stdio",
+        "command": "dotnet",
+        "args": [
+          "run",
+          "--project",
+          "<PATH TO PROJECT DIRECTORY>"
+        ]
+      }
+    }
+  }
+}
+```

src/ProjectTemplates/Microsoft.Extensions.AI.Templates/src/McpServer/McpServer-CSharp/Tools/RandomNumberTools.cs

@@ -0,0 +1,18 @@
+using System.ComponentModel;
+using ModelContextProtocol.Server;
+
+/// <summary>
+/// Sample MCP tools for demonstration purposes.
+/// These tools can be invoked by MCP clients to perform various operations.
+/// </summary>
+internal class RandomNumberTools
+{
+    [McpServerTool(Name = "get_random_number")]
+    [Description("Generates a random number between the specified minimum and maximum values.")]
+    public int GetRandomNumber(
+        [Description("Minimum value (inclusive)")] int min = 0,
+        [Description("Maximum value (exclusive)")] int max = 100)
+    {
+        return Random.Shared.Next(min, max);
+    }
+}

test/ProjectTemplates/Microsoft.Extensions.AI.Templates.IntegrationTests/McpServerSnapshotTests.cs

@@ -0,0 +1,95 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+using Microsoft.Extensions.AI.Templates.Tests;
+using Microsoft.Extensions.Logging;
+using Microsoft.TemplateEngine.Authoring.TemplateVerifier;
+using Microsoft.TemplateEngine.TestHelper;
+using Xunit;
+using Xunit.Abstractions;
+
+namespace Microsoft.Extensions.AI.Templates.Tests;
+
+public class McpServerSnapshotTests
+{
+    // Keep the exclude patterns below in sync with those in Microsoft.Extensions.AI.Templates.csproj.
+    private static readonly string[] _verificationExcludePatterns = [
+        "**/bin/**",
+        "**/obj/**",
+        "**/.vs/**",
+        "**/*.sln",
+        "**/*.in",
+    ];
+
+    private readonly ILogger _log;
+
+    public McpServerSnapshotTests(ITestOutputHelper log)
+    {
+#pragma warning disable CA2000 // Dispose objects before losing scope
+        _log = new XunitLoggerProvider(log).CreateLogger("TestRun");
+#pragma warning restore CA2000 // Dispose objects before losing scope
+    }
+
+    [Fact]
+    public async Task BasicTest()
+    {
+        await TestTemplateCoreAsync(scenarioName: "Basic");
+    }
+
+    private async Task TestTemplateCoreAsync(string scenarioName, IEnumerable<string>? templateArgs = null)
+    {
+        string workingDir = TestUtils.CreateTemporaryFolder();
+        string templateShortName = "mcpserver";
+
+        // Get the template location
+        string templateLocation = Path.Combine(WellKnownPaths.TemplateFeedLocation, "Microsoft.Extensions.AI.Templates", "src", "McpServer");
+
+        var verificationExcludePatterns = Path.DirectorySeparatorChar is '/'
+            ? _verificationExcludePatterns
+            : _verificationExcludePatterns.Select(p => p.Replace('/', Path.DirectorySeparatorChar)).ToArray();
+
+        TemplateVerifierOptions options = new TemplateVerifierOptions(templateName: templateShortName)
+        {
+            TemplatePath = templateLocation,
+            TemplateSpecificArgs = templateArgs,
+            SnapshotsDirectory = "Snapshots",
+            OutputDirectory = workingDir,
+            DoNotPrependCallerMethodNameToScenarioName = true,
+            DoNotAppendTemplateArgsToScenarioName = true,
+            ScenarioName = scenarioName,
+            VerificationExcludePatterns = verificationExcludePatterns,
+        }
+        .WithCustomScrubbers(
+            ScrubbersDefinition.Empty.AddScrubber((path, content) =>
+            {
+                string filePath = path.UnixifyDirSeparators();
+
+                if (filePath.EndsWith(".csproj"))
+                {
+                    // Scrub references to just-built packages and remove the suffix, if it exists.
+                    // This allows the snapshots to remain the same regardless of where the repo is built (e.g., locally, public CI, internal CI).
+                    var pattern = @"(?<=<PackageReference\s+Include=""Microsoft\.Extensions\..*""\s+Version="")(\d+\.\d+\.\d+)(?:-[^""]*)?(?=""\s*/>)";
+                    content.ScrubByRegex(pattern, replacement: "$1");
+                }
+            }));
+
+        VerificationEngine engine = new VerificationEngine(_log);
+        await engine.Execute(options);
+
+#pragma warning disable CA1031 // Do not catch general exception types
+        try
+        {
+            Directory.Delete(workingDir, recursive: true);
+        }
+        catch
+        {
+            /* don't care */
+        }
+#pragma warning restore CA1031 // Do not catch general exception types
+    }
+}