.Net: Mcp sampling sample

dotnet/Directory.Packages.props

@@ -35,7 +35,7 @@
     <PackageVersion Include="Grpc.AspNetCore.Server.Reflection" Version="2.70.0" />
     <PackageVersion Include="Grpc.AspNetCore.Web" Version="2.70.0" />
     <PackageVersion Include="Grpc.Tools" Version="2.70.0" />
-    <PackageVersion Include="ModelContextProtocol" Version="0.1.0-preview.7" />
+    <PackageVersion Include="ModelContextProtocol" Version="0.1.0-preview.8" />
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="8.0.13" />
     <PackageVersion Include="Microsoft.AspNetCore.OpenApi" Version="8.0.14" />
     <PackageVersion Include="Microsoft.ML.Tokenizers.Data.Cl100kBase" Version="1.0.1" />

dotnet/samples/Demos/ModelContextProtocolClientServer/MCPClient/Extensions/AuthorRoleExtensions.cs

@@ -0,0 +1,33 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using Microsoft.SemanticKernel.ChatCompletion;
+using ModelContextProtocol.Protocol.Types;
+
+namespace MCPClient;
+
+/// <summary>
+/// Extension methods for the <see cref="AuthorRole"/>.
+/// </summary>
+internal static class AuthorRoleExtensions
+{
+    /// <summary>
+    /// Converts a <see cref="AuthorRole"/> to a <see cref="Role"/>.
+    /// </summary>
+    /// <param name="role">The author role to convert.</param>
+    /// <returns>The corresponding <see cref="Role"/>.</returns>
+    public static Role ToMCPRole(this AuthorRole role)
+    {
+        if (role == AuthorRole.User)
+        {
+            return Role.User;
+        }
+
+        if (role == AuthorRole.Assistant)
+        {
+            return Role.Assistant;
+        }
+
+        throw new InvalidOperationException($"Unexpected role '{role}'");
+    }
+}

dotnet/samples/Demos/ModelContextProtocolClientServer/MCPClient/Extensions/ChatMessageContentExtensions.cs

@@ -0,0 +1,66 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Linq;
+using Microsoft.SemanticKernel;
+using ModelContextProtocol.Protocol.Types;
+
+namespace MCPClient;
+
+/// <summary>
+/// Extension methods for <see cref="ChatMessageContent"/>.
+/// </summary>
+public static class ChatMessageContentExtensions
+{
+    /// <summary>
+    /// Converts a <see cref="ChatMessageContent"/> to a <see cref="CreateMessageResult"/>.
+    /// </summary>
+    /// <param name="chatMessageContent">The <see cref="ChatMessageContent"/> to convert.</param>
+    /// <returns>The corresponding <see cref="CreateMessageResult"/>.</returns>
+    public static CreateMessageResult ToCreateMessageResult(this ChatMessageContent chatMessageContent)
+    {
+        // Using the same heuristic as in the original MCP SDK code: McpClientExtensions.ToCreateMessageResult for consistency.
+        // ChatMessageContent can contain multiple items of different modalities, while the CreateMessageResult
+        // can only have a single content type: text, image, or audio. First, look for image or audio content,
+        // and if not found, fall back to the text content type by concatenating the text of all text contents.
+        Content? content = null;
+
+        foreach (KernelContent item in chatMessageContent.Items)
+        {
+            if (item is ImageContent image)
+            {
+                content = new Content
+                {
+                    Type = "image",
+                    Data = Convert.ToBase64String(image.Data!.Value.Span),
+                    MimeType = image.MimeType
+                };
+                break;
+            }
+            else if (item is AudioContent audio)
+            {
+                content = new Content
+                {
+                    Type = "audio",
+                    Data = Convert.ToBase64String(audio.Data!.Value.Span),
+                    MimeType = audio.MimeType
+                };
+                break;
+            }
+        }
+
+        content ??= new Content
+        {
+            Type = "text",
+            Text = string.Concat(chatMessageContent.Items.OfType<TextContent>()),
+            MimeType = "text/plain"
+        };
+
+        return new CreateMessageResult
+        {
+            Role = chatMessageContent.Role.ToMCPRole(),
+            Model = chatMessageContent.ModelId ?? "unknown",
+            Content = content
+        };
+    }
+}

dotnet/samples/Demos/ModelContextProtocolClientServer/MCPClient/Extensions/ContentExtensions.cs

@@ -0,0 +1,29 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using Microsoft.SemanticKernel;
+using ModelContextProtocol.Protocol.Types;
+
+namespace MCPClient;
+
+/// <summary>
+/// Extension methods for the <see cref="Content"/> class.
+/// </summary>
+public static class ContentExtensions
+{
+    /// <summary>
+    /// Converts a <see cref="Content"/> object to a <see cref="KernelContent"/> object.
+    /// </summary>
+    /// <param name="content">The <see cref="Content"/> object to convert.</param>
+    /// <returns>The corresponding <see cref="KernelContent"/> object.</returns>
+    public static KernelContent ToKernelContent(this Content content)
+    {
+        return content.Type switch
+        {
+            "text" => new TextContent(content.Text),
+            "image" => new ImageContent(Convert.FromBase64String(content.Data!), content.MimeType),
+            "audio" => new AudioContent(Convert.FromBase64String(content.Data!), content.MimeType),
+            _ => throw new InvalidOperationException($"Unexpected message content type '{content.Type}'"),
+        };
+    }
+}

dotnet/samples/Demos/ModelContextProtocolClientServer/MCPClient/Extensions/PromptResultExtensions.cs

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft. All rights reserved.
 
-using System;
 using System.Collections.Generic;
+using System.Linq;
 using Microsoft.SemanticKernel;
 using Microsoft.SemanticKernel.ChatCompletion;
 using ModelContextProtocol.Protocol.Types;
@@ -20,30 +20,16 @@ internal static class PromptResultExtensions
     /// <returns>The corresponding <see cref="ChatHistory"/>.</returns>
     public static IList<ChatMessageContent> ToChatMessageContents(this GetPromptResult result)
     {
-        List<ChatMessageContent> contents = [];
-
-        foreach (PromptMessage message in result.Messages)
-        {
-            ChatMessageContentItemCollection items = [];
-
-            switch (message.Content.Type)
-            {
-                case "text":
-                    items.Add(new TextContent(message.Content.Text));
-                    break;
-                case "image":
-                    items.Add(new ImageContent(Convert.FromBase64String(message.Content.Data!), message.Content.MimeType));
-                    break;
-                case "audio":
-                    items.Add(new AudioContent(Convert.FromBase64String(message.Content.Data!), message.Content.MimeType));
-                    break;
-                default:
-                    throw new InvalidOperationException($"Unexpected message content type '{message.Content.Type}'");
-            }
-
-            contents.Add(new ChatMessageContent(message.Role.ToAuthorRole(), items));
-        }
+        return [.. result.Messages.Select(ToChatMessageContent)];
+    }
 
-        return contents;
+    /// <summary>
+    /// Converts a <see cref="PromptMessage"/> to a <see cref="ChatMessageContent"/>.
+    /// </summary>
+    /// <param name="message">The <see cref="PromptMessage"/> to convert.</param>
+    /// <returns>The corresponding <see cref="ChatMessageContent"/>.</returns>
+    public static ChatMessageContent ToChatMessageContent(this PromptMessage message)
+    {
+        return new ChatMessageContent(role: message.Role.ToAuthorRole(), items: [message.Content.ToKernelContent()]);
     }
 }

dotnet/samples/Demos/ModelContextProtocolClientServer/MCPClient/Extensions/SamplingMessageExtensions.cs

@@ -0,0 +1,34 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.SemanticKernel;
+using ModelContextProtocol.Protocol.Types;
+
+namespace MCPClient;
+
+/// <summary>
+/// Extension methods for <see cref="SamplingMessage"/>.
+/// </summary>
+public static class SamplingMessageExtensions
+{
+    /// <summary>
+    /// Converts a collection of <see cref="SamplingMessage"/> to a list of <see cref="ChatMessageContent"/>.
+    /// </summary>
+    /// <param name="samplingMessages">The collection of <see cref="SamplingMessage"/> to convert.</param>
+    /// <returns>The corresponding list of <see cref="ChatMessageContent"/>.</returns>
+    public static List<ChatMessageContent> ToChatMessageContents(this IEnumerable<SamplingMessage> samplingMessages)
+    {
+        return [.. samplingMessages.Select(ToChatMessageContent)];
+    }
+
+    /// <summary>
+    /// Converts a <see cref="SamplingMessage"/> to a <see cref="ChatMessageContent"/>.
+    /// </summary>
+    /// <param name="message">The <see cref="SamplingMessage"/> to convert.</param>
+    /// <returns>The corresponding <see cref="ChatMessageContent"/>.</returns>
+    public static ChatMessageContent ToChatMessageContent(this SamplingMessage message)
+    {
+        return new ChatMessageContent(role: message.Role.ToAuthorRole(), items: [message.Content.ToKernelContent()]);
+    }
+}

dotnet/samples/Demos/ModelContextProtocolClientServer/MCPClient/HumanInTheLoopFilter.cs

@@ -0,0 +1,48 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Threading.Tasks;
+using Microsoft.SemanticKernel;
+using ModelContextProtocol.Protocol.Types;
+
+namespace MCPClient;
+
+/// <summary>
+/// A filter that intercepts function invocations to allow for human-in-the-loop processing.
+/// </summary>
+public class HumanInTheLoopFilter : IFunctionInvocationFilter
+{
+    /// <inheritdoc />
+    public Task OnFunctionInvocationAsync(FunctionInvocationContext context, Func<FunctionInvocationContext, Task> next)
+    {
+        // Intercept the MCP sampling handler before invoking it
+        if (context.Function.Name == "MCPSamplingHandler")
+        {
+            CreateMessageRequestParams request = (CreateMessageRequestParams)context.Arguments["request"]!;
+
+            if (!GetUserApprovalForSamplingMessages(request))
+            {
+                context.Result = new FunctionResult(context.Result, "Operation was rejected due to PII.");
+                return Task.CompletedTask;
+            }
+        }
+
+        // Proceed with the handler invocation
+        return next.Invoke(context);
+    }
+
+    /// <summary>
+    /// Checks if the user approves the messages for further sampling request processing.
+    /// </summary>
+    /// <remarks>
+    /// This method serves as a placeholder for the actual implementation, which may involve user interaction through a user interface.
+    /// The user will be presented with a list of messages and given two options: to approve or reject the request.
+    /// </remarks>
+    /// <param name="request">The sampling request.</param>
+    /// <returns>Returns true if the user approves; otherwise, false.</returns>
+    private static bool GetUserApprovalForSamplingMessages(CreateMessageRequestParams request)
+    {
+        // Approve the request
+        return true;
+    }
+}