Support alternative package managers in MCP Inspector integration

.devcontainer/devcontainer.json

@@ -15,7 +15,9 @@
       "version": "21"
     },
     "ghcr.io/devcontainers/features/docker-in-docker:2": {},
-    "ghcr.io/devcontainers/features/node:latest": {},
+    "ghcr.io/devcontainers/features/node:latest": {
+      "installYarnUsingApt": false,
+    },
     "ghcr.io/devcontainers-community/features/deno": {},
     "ghcr.io/devcontainers/features/go:latest": {},
     "ghcr.io/devcontainers/features/rust:latest": {},

src/CommunityToolkit.Aspire.Hosting.McpInspector/McpInspectorResource.cs

@@ -6,10 +6,16 @@ namespace Aspire.Hosting.ApplicationModel;
 /// Resource for the MCP Inspector server.
 /// </summary>
 /// <param name="name">The name of the resource.</param>
-public class McpInspectorResource(string name) : JavaScriptAppResource(name, "npx", "")
+/// <param name="packageName">The npm package name for the MCP Inspector.</param>
+public class McpInspectorResource(string name, string packageName) : JavaScriptAppResource(name, "npx", "")
 {
     internal readonly string ConfigPath = Path.GetTempFileName();
 
+    /// <summary>
+    /// Gets the npm package name for the MCP Inspector.
+    /// </summary>
+    internal string PackageName { get; } = packageName;
+
     /// <summary>
     /// The name of the client endpoint.
     /// </summary>

src/CommunityToolkit.Aspire.Hosting.McpInspector/McpInspectorResourceBuilderExtensions.cs

@@ -1,4 +1,5 @@
 using Aspire.Hosting.ApplicationModel;
+using Aspire.Hosting.JavaScript;
 using CommunityToolkit.Hosting.Utils;
 using Microsoft.Extensions.DependencyInjection;
 
@@ -37,18 +38,28 @@ public static IResourceBuilder<McpInspectorResource> AddMcpInspector(this IDistr
     /// <param name="name">The name of the MCP Inspector container resource.</param>
     /// <param name="options">The <see cref="McpInspectorOptions"/> to configure the MCP Inspector resource.</param>
     /// <returns>A reference to the <see cref="IResourceBuilder{McpInspectorResource}"/> for further configuration.</returns>
+    /// <remarks>
+    /// By default, the MCP Inspector uses npm/npx. To use a different package manager, chain the appropriate method:
+    /// <code>
+    /// builder.AddMcpInspector("inspector")
+    ///     .WithYarn();
+    /// </code>
+    /// </remarks>
     public static IResourceBuilder<McpInspectorResource> AddMcpInspector(this IDistributedApplicationBuilder builder, [ResourceName] string name, McpInspectorOptions options)
     {
         ArgumentNullException.ThrowIfNull(builder);
         ArgumentNullException.ThrowIfNull(options);
 
         var proxyTokenParameter = options.ProxyToken?.Resource ?? ParameterResourceBuilderExtensions.CreateDefaultPasswordParameter(builder, $"{name}-proxyToken");
 
-        var resource = builder.AddResource(new McpInspectorResource(name))
-            .WithNpm(install: true, installArgs: ["-y", $"@modelcontextprotocol/inspector@{options.InspectorVersion}", "--no-save", "--no-package-lock"])
-            .WithCommand("npx")
-            .WithArgs(["-y", $"@modelcontextprotocol/inspector@{options.InspectorVersion}"])
+        var packageName = $"@modelcontextprotocol/inspector@{options.InspectorVersion}";
+
+        var resourceBuilder = builder.AddResource(new McpInspectorResource(name, packageName));
+
+        resourceBuilder
             .ExcludeFromManifest()
+            .WithInspectorArgs()
+            .WithDefaultArgs()
             .WithHttpEndpoint(isProxied: false, port: options.ClientPort, env: "CLIENT_PORT", name: McpInspectorResource.ClientEndpointName)
             .WithHttpEndpoint(isProxied: false, port: options.ServerPort, env: "SERVER_PORT", name: McpInspectorResource.ServerProxyEndpointName)
             .WithHttpHealthCheck("/", endpointName: McpInspectorResource.ClientEndpointName)
@@ -108,7 +119,6 @@ public static IResourceBuilder<McpInspectorResource> AddMcpInspector(this IDistr
                 ctx.EnvironmentVariables["SERVER_PORT"] = serverProxyEndpoint.TargetPort?.ToString() ?? throw new InvalidOperationException("The MCP Inspector 'server-proxy' endpoint must have a target port defined.");
                 ctx.EnvironmentVariables["MCP_PROXY_AUTH_TOKEN"] = proxyTokenParameter;
             })
-            .WithDefaultArgs()
             .WithUrls(async context =>
             {
                 var token = await proxyTokenParameter.GetValueAsync(CancellationToken.None);
@@ -126,13 +136,13 @@ public static IResourceBuilder<McpInspectorResource> AddMcpInspector(this IDistr
                 }
             });
 
-        resource.Resource.ProxyTokenParameter = proxyTokenParameter;
+        resourceBuilder.Resource.ProxyTokenParameter = proxyTokenParameter;
 
         // Add authenticated health check for server proxy /config endpoint
         var healthCheckKey = $"{name}_proxy_config_check";
         builder.Services.AddHealthChecks().AddUrlGroup(options =>
         {
-            var serverProxyEndpoint = resource.GetEndpoint(McpInspectorResource.ServerProxyEndpointName);
+            var serverProxyEndpoint = resourceBuilder.GetEndpoint(McpInspectorResource.ServerProxyEndpointName);
             var uri = serverProxyEndpoint.Url ?? throw new DistributedApplicationException("The MCP Inspector 'server-proxy' endpoint URL is not set. Ensure that the resource has been allocated before the health check is executed.");
             var healthCheckUri = new Uri(new Uri(uri), "/config");
             options.AddUri(healthCheckUri, async setup =>
@@ -143,7 +153,7 @@ public static IResourceBuilder<McpInspectorResource> AddMcpInspector(this IDistr
         }, healthCheckKey);
         builder.Services.SuppressHealthCheckHttpClientLogging(healthCheckKey);
 
-        return resource.WithHealthCheck(healthCheckKey);
+        return resourceBuilder.WithHealthCheck(healthCheckKey);
     }
 
     /// <summary>
@@ -261,4 +271,54 @@ internal static Uri Combine(string baseUrl, params string[] segments)
 
         return new Uri(baseUri, relative);
     }
+
+    /// <summary>
+    /// Sets up the command and arguments for the MCP Inspector based on the configured package manager.
+    /// </summary>
+    private static IResourceBuilder<McpInspectorResource> WithInspectorArgs(this IResourceBuilder<McpInspectorResource> builder)
+    {
+        return builder.WithArgs(ctx =>
+        {
+            var resource = builder.Resource;
+            var packageName = resource.PackageName;
+
+            // Add the appropriate arguments based on the package manager
+            switch (resource.Command)
+            {
+                case "yarn":
+                case "pnpm":
+                    ctx.Args.Insert(0, packageName);
+                    ctx.Args.Insert(0, "dlx");
+                    break;
+                default: // npm/npx
+                    ctx.Args.Insert(0, packageName);
+                    ctx.Args.Insert(0, "-y");
+                    break;
+            }
+        });
+    }
+
+    /// <summary>
+    /// Configures the MCP Inspector to use yarn as the package manager.
+    /// </summary>
+    /// <param name="builder">The MCP Inspector resource builder.</param>
+    /// <returns>A reference to the <see cref="IResourceBuilder{T}"/>.</returns>
+    public static IResourceBuilder<McpInspectorResource> WithYarn(this IResourceBuilder<McpInspectorResource> builder)
+    {
+        ArgumentNullException.ThrowIfNull(builder);
+
+        return builder.WithCommand("yarn");
+    }
+
+    /// <summary>
+    /// Configures the MCP Inspector to use pnpm as the package manager.
+    /// </summary>
+    /// <param name="builder">The MCP Inspector resource builder.</param>
+    /// <returns>A reference to the <see cref="IResourceBuilder{T}"/>.</returns>
+    public static IResourceBuilder<McpInspectorResource> WithPnpm(this IResourceBuilder<McpInspectorResource> builder)
+    {
+        ArgumentNullException.ThrowIfNull(builder);
+
+        return builder.WithCommand("pnpm");
+    }
 }

src/CommunityToolkit.Aspire.Hosting.McpInspector/README.md

@@ -25,6 +25,24 @@ var inspector = builder.AddMcpInspector("inspector")
 
 You can specify the transport type (`StreamableHttp`) and set which server is the default for the inspector.
 
+#### Using alternative package managers
+
+By default, the MCP Inspector uses npm/npx. You can configure it to use yarn or pnpm instead by chaining the appropriate method:
+
+```csharp
+// Using yarn
+var inspector = builder.AddMcpInspector("inspector")
+    .WithYarn()
+    .WithMcpServer(mcpServer);
+
+// Using pnpm
+var inspector = builder.AddMcpInspector("inspector")
+    .WithPnpm()
+    .WithMcpServer(mcpServer);
+```
+
+When using yarn or pnpm, the inspector will use `yarn dlx` or `pnpm dlx` respectively to run the MCP Inspector package.
+
 #### Using options for complex configurations
 
 For more complex configurations with multiple parameters, you can use the options-based approach:
@@ -60,7 +78,7 @@ var inspector = builder.AddMcpInspector("inspector", options =>
 
 The `McpInspectorOptions` class provides the following configuration properties:
 
--   `ClientPort`: Port for the client application (default: 6274
+-   `ClientPort`: Port for the client application (default: 6274)
 -   `ServerPort`: Port for the server proxy application (default: 6277)
 -   `InspectorVersion`: Version of the Inspector app to use (default: latest supported version)
 -   `ProxyToken`: Custom authentication token parameter (default: auto-generated)

tests/CommunityToolkit.Aspire.Hosting.McpInspector.Tests/McpInspectorResourceBuilderExtensionsTests.cs

@@ -1,5 +1,6 @@
 using Aspire.Hosting;
 using Aspire.Hosting.ApplicationModel;
+using Aspire.Hosting.JavaScript;
 
 namespace CommunityToolkit.Aspire.Hosting.McpInspector.Tests;
 
@@ -491,4 +492,167 @@ public void WithMcpServerWithBothEndpointsUsesHttps()
         // Verify the endpoint is the https one (preferred when both exist)
         Assert.Equal("https", serverMetadata.Endpoint.EndpointName);
     }
+
+    [Fact]
+    public void AddMcpInspectorDefaultsToNpx()
+    {
+        // Arrange
+        var appBuilder = DistributedApplication.CreateBuilder();
+
+        // Act
+        var inspector = appBuilder.AddMcpInspector("inspector");
+
+        using var app = appBuilder.Build();
+
+        // Assert
+        var appModel = app.Services.GetRequiredService<DistributedApplicationModel>();
+        var inspectorResource = Assert.Single(appModel.Resources.OfType<McpInspectorResource>());
+
+        // Default command is npx (set in constructor)
+        Assert.Equal("npx", inspectorResource.Command);
+    }
+
+    [Fact]
+    public void WithYarnSetsCommand()
+    {
+        // Arrange
+        var appBuilder = DistributedApplication.CreateBuilder();
+
+        // Act
+        var inspector = appBuilder.AddMcpInspector("inspector")
+            .WithYarn();
+
+        using var app = appBuilder.Build();
+
+        // Assert
+        var appModel = app.Services.GetRequiredService<DistributedApplicationModel>();
+        var inspectorResource = Assert.Single(appModel.Resources.OfType<McpInspectorResource>());
+
+        Assert.Equal("yarn", inspectorResource.Command);
+    }
+
+    [Fact]
+    public void WithPnpmSetsCommand()
+    {
+        // Arrange
+        var appBuilder = DistributedApplication.CreateBuilder();
+
+        // Act
+        var inspector = appBuilder.AddMcpInspector("inspector")
+            .WithPnpm();
+
+        using var app = appBuilder.Build();
+
+        // Assert
+        var appModel = app.Services.GetRequiredService<DistributedApplicationModel>();
+        var inspectorResource = Assert.Single(appModel.Resources.OfType<McpInspectorResource>());
+
+        Assert.Equal("pnpm", inspectorResource.Command);
+    }
+
+    [Fact]
+    public async Task WithYarnSetsCorrectArguments()
+    {
+        // Arrange
+        var appBuilder = DistributedApplication.CreateBuilder();
+
+        // Act
+        var inspector = appBuilder.AddMcpInspector("inspector", options =>
+        {
+            options.InspectorVersion = "0.15.0";
+        })
+            .WithYarn();
+
+        using var app = appBuilder.Build();
+
+        // Assert
+        var appModel = app.Services.GetRequiredService<DistributedApplicationModel>();
+        var inspectorResource = Assert.Single(appModel.Resources.OfType<McpInspectorResource>());
+
+        var args = await inspectorResource.GetArgumentValuesAsync();
+        var argsList = args.ToList();
+
+        // For yarn, the first arg should be "dlx"
+        Assert.Equal("dlx", argsList[0]);
+        Assert.Equal("@modelcontextprotocol/inspector@0.15.0", argsList[1]);
+    }
+
+    [Fact]
+    public async Task WithPnpmSetsCorrectArguments()
+    {
+        // Arrange
+        var appBuilder = DistributedApplication.CreateBuilder();
+
+        // Act
+        var inspector = appBuilder.AddMcpInspector("inspector", options =>
+        {
+            options.InspectorVersion = "0.15.0";
+        })
+            .WithPnpm();
+
+        using var app = appBuilder.Build();
+
+        // Assert
+        var appModel = app.Services.GetRequiredService<DistributedApplicationModel>();
+        var inspectorResource = Assert.Single(appModel.Resources.OfType<McpInspectorResource>());
+
+        var args = await inspectorResource.GetArgumentValuesAsync();
+        var argsList = args.ToList();
+
+        // For pnpm, the first arg should be "dlx"
+        Assert.Equal("dlx", argsList[0]);
+        Assert.Equal("@modelcontextprotocol/inspector@0.15.0", argsList[1]);
+    }
+
+    [Fact]
+    public async Task DefaultNpxUsesCorrectArguments()
+    {
+        // Arrange
+        var appBuilder = DistributedApplication.CreateBuilder();
+
+        // Act
+        var inspector = appBuilder.AddMcpInspector("inspector", options =>
+        {
+            options.InspectorVersion = "0.15.0";
+        });
+
+        using var app = appBuilder.Build();
+
+        // Assert
+        var appModel = app.Services.GetRequiredService<DistributedApplicationModel>();
+        var inspectorResource = Assert.Single(appModel.Resources.OfType<McpInspectorResource>());
+
+        var args = await inspectorResource.GetArgumentValuesAsync();
+        var argsList = args.ToList();
+
+        // For npm/npx, the first arg should be "-y"
+        Assert.Equal("-y", argsList[0]);
+        Assert.Equal("@modelcontextprotocol/inspector@0.15.0", argsList[1]);
+    }
+
+    [Fact]
+    public async Task AddMcpInspectorWithOptionsRespectsInspectorVersion()
+    {
+        // Arrange
+        var appBuilder = DistributedApplication.CreateBuilder();
+
+        var options = new McpInspectorOptions
+        {
+            InspectorVersion = "1.2.3"
+        };
+
+        // Act
+        var inspector = appBuilder.AddMcpInspector("inspector", options);
+
+        using var app = appBuilder.Build();
+
+        // Assert
+        var appModel = app.Services.GetRequiredService<DistributedApplicationModel>();
+        var inspectorResource = Assert.Single(appModel.Resources.OfType<McpInspectorResource>());
+
+        var args = await inspectorResource.GetArgumentValuesAsync();
+        var argsList = args.ToList();
+
+        Assert.Equal("@modelcontextprotocol/inspector@1.2.3", argsList[1]);
+    }
 }