Resource capability (#5)

Prompt capability
Pagination support

src/mcpdotnet.Tests/IntegrationTests.cs

@@ -2,11 +2,13 @@
 using McpDotNet.Configuration;
 using McpDotNet.Protocol.Messages;
 using McpDotNet.Protocol.Transport;
+using McpDotNet.Protocol.Types;
 using Moq;
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
+using System.Net.Mail;
 using System.Text;
 using System.Threading.Channels;
 using System.Threading.Tasks;
@@ -73,7 +75,7 @@ public class IntegrationTests
 
         // act
         var client = await factory.GetClientAsync("everything");
-        var tools = await client.ListToolsAsync(CancellationToken.None);
+        var tools = await client.ListToolsAsync();
 
         // assert
         Assert.NotNull(tools);
@@ -119,4 +121,224 @@ public class IntegrationTests
         var textContent = Assert.Single(result.Content.Where(c => c.Type == "text"));
         Assert.Equal("Echo: Hello MCP!", textContent.Text);
     }
+
+    [Fact]
+    public async Task ListPrompts_Stdio_EverythingServer()
+    {
+        // arrange
+        var config = new McpServerConfig
+        {
+            Id = "everything",
+            Name = "Everything",
+            TransportType = "stdio",
+            TransportOptions = new Dictionary<string, string>
+            {
+                ["command"] = "npx",
+                ["arguments"] = "-y @modelcontextprotocol/server-everything"
+            }
+        };
+
+        var factory = new McpClientFactory(
+            new[] { config },
+            _defaultOptions
+        );
+
+        var client = await factory.GetClientAsync("everything");
+        var prompts = await client.ListPromptsAsync();
+
+        // assert
+        Assert.NotNull(prompts);
+        Assert.NotEmpty(prompts.Prompts);
+        // We could add specific assertions for the known prompts
+        Assert.Contains(prompts.Prompts, p => p.Name == "simple_prompt");
+        Assert.Contains(prompts.Prompts, p => p.Name == "complex_prompt");
+    }
+
+    [Fact]
+    public async Task GetPrompt_Stdio_SimplePrompt()
+    {
+        // arrange
+        var config = new McpServerConfig
+        {
+            Id = "everything",
+            Name = "Everything",
+            TransportType = "stdio",
+            TransportOptions = new Dictionary<string, string>
+            {
+                ["command"] = "npx",
+                ["arguments"] = "-y @modelcontextprotocol/server-everything"
+            }
+        };
+
+        var factory = new McpClientFactory(
+            new[] { config },
+            _defaultOptions
+        );
+
+        var client = await factory.GetClientAsync("everything");
+        var result = await client.GetPromptAsync("simple_prompt", null, CancellationToken.None);
+
+        // assert
+        Assert.NotNull(result);
+        Assert.NotEmpty(result.Messages);
+    }
+
+    [Fact]
+    public async Task GetPrompt_Stdio_ComplexPrompt()
+    {
+        // arrange
+        var config = new McpServerConfig
+        {
+            Id = "everything",
+            Name = "Everything",
+            TransportType = "stdio",
+            TransportOptions = new Dictionary<string, string>
+            {
+                ["command"] = "npx",
+                ["arguments"] = "-y @modelcontextprotocol/server-everything"
+            }
+        };
+
+        var factory = new McpClientFactory(
+            new[] { config },
+            _defaultOptions
+        );
+
+        var client = await factory.GetClientAsync("everything");
+        var arguments = new Dictionary<string, object>
+        {
+            { "temperature", "0.7" },
+            { "style", "formal" }
+        };
+        var result = await client.GetPromptAsync("complex_prompt", arguments, CancellationToken.None);
+
+        // assert
+        Assert.NotNull(result);
+        Assert.NotEmpty(result.Messages);
+    }
+
+    [Fact]
+    public async Task GetPrompt_NonExistent_ThrowsException()
+    {
+        // arrange
+        var config = new McpServerConfig
+        {
+            Id = "everything",
+            Name = "Everything",
+            TransportType = "stdio",
+            TransportOptions = new Dictionary<string, string>
+            {
+                ["command"] = "npx",
+                ["arguments"] = "-y @modelcontextprotocol/server-everything"
+            }
+        };
+
+        var factory = new McpClientFactory(
+            new[] { config },
+            _defaultOptions
+        );
+
+        var client = await factory.GetClientAsync("everything");
+        await Assert.ThrowsAsync<McpClientException>(() =>
+            client.GetPromptAsync("non_existent_prompt", null, CancellationToken.None));
+    }
+
+    [Fact]
+    public async Task ListResources_Stdio_EverythingServer()
+    {
+        // arrange
+        var config = new McpServerConfig
+        {
+            Id = "everything",
+            Name = "Everything",
+            TransportType = "stdio",
+            TransportOptions = new Dictionary<string, string>
+            {
+                ["command"] = "npx",
+                ["arguments"] = "-y @modelcontextprotocol/server-everything"
+            }
+        };
+
+        var factory = new McpClientFactory(
+            new[] { config },
+            _defaultOptions
+        );
+
+        var client = await factory.GetClientAsync("everything");
+
+        List<Resource> allResources = new();
+        string? cursor = null;
+        do
+        {
+            var resources = await client.ListResourcesAsync(cursor, CancellationToken.None);
+            allResources.AddRange(resources.Resources);
+            cursor = resources.NextCursor;
+        }
+        while (cursor != null);
+
+        // The everything server provides 100 test resources
+        Assert.Equal(100, allResources.Count);
+    }
+
+    [Fact]
+    public async Task ReadResource_Stdio_TextResource()
+    {
+        // arrange
+        var config = new McpServerConfig
+        {
+            Id = "everything",
+            Name = "Everything",
+            TransportType = "stdio",
+            TransportOptions = new Dictionary<string, string>
+            {
+                ["command"] = "npx",
+                ["arguments"] = "-y @modelcontextprotocol/server-everything"
+            }
+        };
+
+        var factory = new McpClientFactory(
+            new[] { config },
+            _defaultOptions
+        );
+
+        var client = await factory.GetClientAsync("everything");
+        // Odd numbered resources are text in the everything server (despite the docs saying otherwise)
+        // 1 is index 0, which is "even" in the 0-based index
+        var result = await client.ReadResourceAsync("test://static/resource/1", CancellationToken.None);
+
+        Assert.NotNull(result);
+        Assert.Single(result.Contents);
+        Assert.NotNull(result.Contents[0].Text);
+    }
+
+    [Fact]
+    public async Task ReadResource_Stdio_BinaryResource()
+    {
+        // arrange
+        var config = new McpServerConfig
+        {
+            Id = "everything",
+            Name = "Everything",
+            TransportType = "stdio",
+            TransportOptions = new Dictionary<string, string>
+            {
+                ["command"] = "npx",
+                ["arguments"] = "-y @modelcontextprotocol/server-everything"
+            }
+        };
+
+        var factory = new McpClientFactory(
+            new[] { config },
+            _defaultOptions
+        );
+
+        var client = await factory.GetClientAsync("everything");
+        // Even numbered resources are binary in the everything server (despite the docs saying otherwise)
+        // 2 is index 1, which is "odd" in the 0-based index
+        var result = await client.ReadResourceAsync("test://static/resource/2", CancellationToken.None);
+
+        Assert.NotNull(result);
+        Assert.Single(result.Contents);
+        Assert.NotNull(result.Contents[0].Blob);
+    }
 }

src/mcpdotnet/Client/IMcpClient.cs

@@ -42,9 +42,10 @@ public interface IMcpClient : IAsyncDisposable
     /// <summary>
     /// Retrieves a list of available tools from the server.
     /// </summary>
+    /// <param name="cursor">An optional cursor to paginate the results.</param>
     /// <param name="cancellationToken">A token to cancel the operation.</param>
     /// <returns>A task containing the server's response with tool information.</returns>
-    Task<ListToolsResponse> ListToolsAsync(CancellationToken cancellationToken = default);
+    Task<ListToolsResult> ListToolsAsync(string? cursor = null, CancellationToken cancellationToken = default);
 
     /// <summary>
     /// Invokes a tool on the server with optional arguments.
@@ -55,6 +56,55 @@ public interface IMcpClient : IAsyncDisposable
     /// <returns>A task containing the tool's response.</returns>
     Task<CallToolResponse> CallToolAsync(string toolName, Dictionary<string, object>? arguments = null, CancellationToken cancellationToken = default);
 
+    /// <summary>
+    /// Retrieves a list of available prompts from the server.
+    /// </summary>
+    /// <param name="cursor">An optional cursor to paginate the results.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns>A task containing the server's response with prompt information.</returns>
+    Task<ListPromptsResult> ListPromptsAsync(string? cursor = null, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Retrieves a specific prompt with optional arguments.
+    /// </summary>
+    /// <param name="name">The name of the prompt to retrieve</param>
+    /// <param name="arguments">Optional arguments for the prompt</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns>A task containing the prompt's content and messages.</returns>
+    Task<GetPromptResult> GetPromptAsync(string name, Dictionary<string, object>? arguments = null, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Retrieves a list of available resources from the server.
+    /// </summary>
+    /// <param name="cursor">An optional cursor to paginate the results.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns></returns>
+    Task<ListResourcesResult> ListResourcesAsync(string? cursor = null, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Reads a resource from the server.
+    /// </summary>
+    /// <param name="uri">The uri of the resource.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns></returns>
+    Task<ReadResourceResult> ReadResourceAsync(string uri, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Subscribes to a resource on the server.
+    /// </summary>
+    /// <param name="uri">The uri of the resource.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns></returns>
+    Task SubscribeToResourceAsync(string uri, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Unsubscribes from a resource on the server.
+    /// </summary>
+    /// <param name="uri">The uri of the resource.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns></returns>
+    Task UnsubscribeFromResourceAsync(string uri, CancellationToken cancellationToken = default);
+
     /// <summary>
     /// Sends a generic JSON-RPC request to the server.
     /// </summary>
@@ -66,6 +116,8 @@ public interface IMcpClient : IAsyncDisposable
 
     /// <summary>
     /// Registers a handler for server notifications of a specific method.
+    /// 
+    /// <see cref="NotificationMethods">Constants for common notification methods</see>
     /// </summary>
     /// <param name="method">The notification method to handle.</param>
     /// <param name="handler">The async handler function to process notifications.</param>

src/mcpdotnet/Client/McpClient.cs

@@ -7,6 +7,7 @@ using McpDotNet.Protocol.Messages;
 using System.Diagnostics;
 using System.Text.Json;
 using McpDotNet.Utils.Json;
+using System.Xml.Linq;
 
 /// <inheritdoc/>
 internal class McpClient : IMcpClient
@@ -135,13 +136,102 @@ internal class McpClient : IMcpClient
     }
 
     /// <inheritdoc/>
-    public async Task<ListToolsResponse> ListToolsAsync(CancellationToken cancellationToken)
+    public async Task<ListToolsResult> ListToolsAsync(string? cursor = null, CancellationToken cancellationToken = default)
     {
-        return await SendRequestAsync<ListToolsResponse>(
+        return await SendRequestAsync<ListToolsResult>(
             new JsonRpcRequest
             {
                 Method = "tools/list",
-                // No parameters needed for tools/list
+                Params = cursor != null ? new Dictionary<string, object?> { ["cursor"] = cursor } : null
+            },
+            cancellationToken
+        ).ConfigureAwait(false);
+    }
+
+    /// <inheritdoc/>
+    public async Task<ListPromptsResult> ListPromptsAsync(string? cursor = null, CancellationToken cancellationToken = default)
+    {
+        return await SendRequestAsync<ListPromptsResult>(
+            new JsonRpcRequest
+            {
+                Method = "prompts/list",
+                Params = cursor != null ? new Dictionary<string, object?> { ["cursor"] = cursor } : null
+            },
+            cancellationToken
+        ).ConfigureAwait(false);
+    }
+
+    /// <inheritdoc/>
+    public async Task<GetPromptResult> GetPromptAsync(string name, Dictionary<string, object>? arguments = null, CancellationToken cancellationToken = default)
+    {
+        return await SendRequestAsync<GetPromptResult>(
+            new JsonRpcRequest
+            {
+                Method = "prompts/get",
+                Params = CreateParametersDictionary(name, arguments)
+            },
+            cancellationToken
+        ).ConfigureAwait(false);
+    }
+
+    /// <inheritdoc/>
+    public async Task<ListResourcesResult> ListResourcesAsync(string? cursor = null, CancellationToken cancellationToken = default)
+    {
+        return await SendRequestAsync<ListResourcesResult>(
+            new JsonRpcRequest
+            {
+                Method = "resources/list",
+                Params = cursor != null ? new Dictionary<string, object?> { ["cursor"] = cursor } : null
+            },
+            cancellationToken
+        ).ConfigureAwait(false);
+    }
+
+    /// <inheritdoc/>
+    public async Task<ReadResourceResult> ReadResourceAsync(string uri, CancellationToken cancellationToken = default)
+    {
+        return await SendRequestAsync<ReadResourceResult>(
+            new JsonRpcRequest
+            {
+                Method = "resources/read",
+                Params = new Dictionary<string, object?>
+                {
+                    ["uri"] = uri
+                }
+            },
+            cancellationToken
+        ).ConfigureAwait(false);
+    }
+
+
+    /// <inheritdoc/>
+    public async Task SubscribeToResourceAsync(string uri, CancellationToken cancellationToken = default)
+    {
+        await SendRequestAsync<dynamic>(
+            new JsonRpcRequest
+            {
+                Method = "resources/subscribe",
+                Params = new Dictionary<string, object?>
+                {
+                    ["uri"] = uri
+                }
+            },
+            cancellationToken
+        ).ConfigureAwait(false);
+    }
+
+
+    /// <inheritdoc/>
+    public async Task UnsubscribeFromResourceAsync(string uri, CancellationToken cancellationToken = default)
+    {
+        await SendRequestAsync<dynamic>(
+            new JsonRpcRequest
+            {
+                Method = "resources/unsubscribe",
+                Params = new Dictionary<string, object?>
+                {
+                    ["uri"] = uri
+                }
             },
             cancellationToken
         ).ConfigureAwait(false);
@@ -155,16 +245,27 @@ internal class McpClient : IMcpClient
             new JsonRpcRequest
             {
                 Method = "tools/call",
-                Params = new Dictionary<string, object?>
-                {
-                    ["name"] = toolName,
-                    ["arguments"] = arguments
-                }
+                Params = CreateParametersDictionary(toolName, arguments)
             },
             cancellationToken
         ).ConfigureAwait(false);
     }
 
+    private static Dictionary<string, object> CreateParametersDictionary(string nameParameter, Dictionary<string, object>? optionalArguments = null)
+    {
+        var parameters = new Dictionary<string, object?>
+        {
+            ["name"] = nameParameter
+        };
+
+        if (optionalArguments != null)
+        {
+            parameters["arguments"] = optionalArguments;
+        }
+
+        return parameters;
+    }
+
     private async Task ProcessMessagesAsync(CancellationToken cancellationToken)
     {
         try

src/mcpdotnet/Protocol/Messages/IJsonRpcMessage.cs

@@ -0,0 +1,12 @@
+namespace McpDotNet.Protocol.Messages;
+
+/// <summary>
+/// Base interface for all JSON-RPC messages in the MCP protocol.
+/// </summary>
+public interface IJsonRpcMessage
+{
+    /// <summary>
+    /// JSON-RPC protocol version. Must be "2.0".
+    /// </summary>
+    string JsonRpc { get; }
+}

src/mcpdotnet/Protocol/Messages/IJsonRpcMessageWithId.cs

@@ -0,0 +1,12 @@
+namespace McpDotNet.Protocol.Messages;
+
+/// <summary>
+/// Base interface for JSON-RPC messages that include an ID.
+/// </summary>
+public interface IJsonRpcMessageWithId : IJsonRpcMessage
+{
+    /// <summary>
+    /// The message identifier.
+    /// </summary>
+    RequestId Id { get; }
+}

src/mcpdotnet/Protocol/Messages/JsonRpcError.cs

@@ -0,0 +1,27 @@
+namespace McpDotNet.Protocol.Messages;
+
+using System.Text.Json.Serialization;
+
+/// <summary>
+/// An error response message in the JSON-RPC protocol.
+/// </summary>
+public record JsonRpcError : IJsonRpcMessageWithId
+{
+    /// <summary>
+    /// JSON-RPC protocol version. Always "2.0".
+    /// </summary>
+    [JsonPropertyName("jsonrpc")]
+    public string JsonRpc { get; init; } = "2.0";
+
+    /// <summary>
+    /// Request identifier matching the original request.
+    /// </summary>
+    [JsonPropertyName("id")]
+    public required RequestId Id { get; init; }
+
+    /// <summary>
+    /// Error information.
+    /// </summary>
+    [JsonPropertyName("error")]
+    public required JsonRpcErrorDetail Error { get; init; }
+}

src/mcpdotnet/Protocol/Messages/JsonRpcErrorDetail.cs

@@ -0,0 +1,27 @@
+namespace McpDotNet.Protocol.Messages;
+
+using System.Text.Json.Serialization;
+
+/// <summary>
+/// Detailed error information for JSON-RPC error responses.
+/// </summary>
+public record JsonRpcErrorDetail
+{
+    /// <summary>
+    /// Integer error code.
+    /// </summary>
+    [JsonPropertyName("code")]
+    public required int Code { get; init; }
+
+    /// <summary>
+    /// Short description of the error.
+    /// </summary>
+    [JsonPropertyName("message")]
+    public required string Message { get; init; }
+
+    /// <summary>
+    /// Optional additional error data.
+    /// </summary>
+    [JsonPropertyName("data")]
+    public object? Data { get; init; }
+}

src/mcpdotnet/Protocol/Messages/JsonRpcMessage.cs

@@ -2,28 +2,6 @@
 
 using System.Text.Json.Serialization;
 
-/// <summary>
-/// Base interface for all JSON-RPC messages in the MCP protocol.
-/// </summary>
-public interface IJsonRpcMessage
-{
-    /// <summary>
-    /// JSON-RPC protocol version. Must be "2.0".
-    /// </summary>
-    string JsonRpc { get; }
-}
-
-/// <summary>
-/// Base interface for JSON-RPC messages that include an ID.
-/// </summary>
-public interface IJsonRpcMessageWithId : IJsonRpcMessage
-{
-    /// <summary>
-    /// The message identifier.
-    /// </summary>
-    RequestId Id { get; }
-}
-
 /// <summary>
 /// A request message in the JSON-RPC protocol.
 /// </summary>
@@ -53,99 +31,3 @@ public record JsonRpcRequest : IJsonRpcMessageWithId
     [JsonPropertyName("params")]
     public object? Params { get; init; }
 }
-
-/// <summary>
-/// A notification message in the JSON-RPC protocol (a request that doesn't expect a response).
-/// </summary>
-public record JsonRpcNotification : IJsonRpcMessage
-{
-    /// <summary>
-    /// JSON-RPC protocol version. Always "2.0".
-    /// </summary>
-    [JsonPropertyName("jsonrpc")]
-    public string JsonRpc { get; init; } = "2.0";
-
-    /// <summary>
-    /// Name of the notification method.
-    /// </summary>
-    [JsonPropertyName("method")]
-    public required string Method { get; init; }
-
-    /// <summary>
-    /// Optional parameters for the notification.
-    /// </summary>
-    [JsonPropertyName("params")]
-    public object? Params { get; init; }
-}
-
-/// <summary>
-/// A successful response message in the JSON-RPC protocol.
-/// </summary>
-public record JsonRpcResponse : IJsonRpcMessageWithId
-{
-    /// <summary>
-    /// JSON-RPC protocol version. Always "2.0".
-    /// </summary>
-    [JsonPropertyName("jsonrpc")]
-    public string JsonRpc { get; init; } = "2.0";
-
-    /// <summary>
-    /// Request identifier matching the original request.
-    /// </summary>
-    [JsonPropertyName("id")]
-    public required RequestId Id { get; init; }
-
-    /// <summary>
-    /// The result of the method invocation.
-    /// </summary>
-    [JsonPropertyName("result")]
-    public required object Result { get; init; }
-}
-
-/// <summary>
-/// An error response message in the JSON-RPC protocol.
-/// </summary>
-public record JsonRpcError : IJsonRpcMessageWithId
-{
-    /// <summary>
-    /// JSON-RPC protocol version. Always "2.0".
-    /// </summary>
-    [JsonPropertyName("jsonrpc")]
-    public string JsonRpc { get; init; } = "2.0";
-
-    /// <summary>
-    /// Request identifier matching the original request.
-    /// </summary>
-    [JsonPropertyName("id")]
-    public required RequestId Id { get; init; }
-
-    /// <summary>
-    /// Error information.
-    /// </summary>
-    [JsonPropertyName("error")]
-    public required JsonRpcErrorDetail Error { get; init; }
-}
-
-/// <summary>
-/// Detailed error information for JSON-RPC error responses.
-/// </summary>
-public record JsonRpcErrorDetail
-{
-    /// <summary>
-    /// Integer error code.
-    /// </summary>
-    [JsonPropertyName("code")]
-    public required int Code { get; init; }
-
-    /// <summary>
-    /// Short description of the error.
-    /// </summary>
-    [JsonPropertyName("message")]
-    public required string Message { get; init; }
-
-    /// <summary>
-    /// Optional additional error data.
-    /// </summary>
-    [JsonPropertyName("data")]
-    public object? Data { get; init; }
-}

src/mcpdotnet/Protocol/Messages/JsonRpcNotification.cs

@@ -0,0 +1,27 @@
+namespace McpDotNet.Protocol.Messages;
+
+using System.Text.Json.Serialization;
+
+/// <summary>
+/// A notification message in the JSON-RPC protocol (a request that doesn't expect a response).
+/// </summary>
+public record JsonRpcNotification : IJsonRpcMessage
+{
+    /// <summary>
+    /// JSON-RPC protocol version. Always "2.0".
+    /// </summary>
+    [JsonPropertyName("jsonrpc")]
+    public string JsonRpc { get; init; } = "2.0";
+
+    /// <summary>
+    /// Name of the notification method.
+    /// </summary>
+    [JsonPropertyName("method")]
+    public required string Method { get; init; }
+
+    /// <summary>
+    /// Optional parameters for the notification.
+    /// </summary>
+    [JsonPropertyName("params")]
+    public object? Params { get; init; }
+}

src/mcpdotnet/Protocol/Messages/JsonRpcResponse.cs

@@ -0,0 +1,27 @@
+namespace McpDotNet.Protocol.Messages;
+
+using System.Text.Json.Serialization;
+
+/// <summary>
+/// A successful response message in the JSON-RPC protocol.
+/// </summary>
+public record JsonRpcResponse : IJsonRpcMessageWithId
+{
+    /// <summary>
+    /// JSON-RPC protocol version. Always "2.0".
+    /// </summary>
+    [JsonPropertyName("jsonrpc")]
+    public string JsonRpc { get; init; } = "2.0";
+
+    /// <summary>
+    /// Request identifier matching the original request.
+    /// </summary>
+    [JsonPropertyName("id")]
+    public required RequestId Id { get; init; }
+
+    /// <summary>
+    /// The result of the method invocation.
+    /// </summary>
+    [JsonPropertyName("result")]
+    public required object Result { get; init; }
+}

src/mcpdotnet/Protocol/Messages/NotificationMethods.cs

@@ -0,0 +1,27 @@
+namespace McpDotNet.Protocol.Messages;
+
+/// <summary>
+/// A class containing constants for notification methods.
+/// </summary>
+public static class NotificationMethods
+{
+    /// <summary>
+    /// Sent by the server when the list of tools changes.
+    /// </summary>
+    public const string ToolListChangedNotification = "notifications/tools/list_changed";
+
+    /// <summary>
+    /// Sent by the server when the list of prompts changes.
+    /// </summary>
+    public const string PromptsListChanged = "notifications/prompts/list_changed";
+
+    /// <summary>
+    /// Sent by the server when the list of resources changes.
+    /// </summary>
+    public const string ResourceListChangedNotification = "notifications/resources/list_changed";
+
+    /// <summary>
+    /// Sent by the server when a resource is updated.
+    /// </summary>
+    public const string ResourceUpdatedNotification = "notifications/resources/updated";
+}

src/mcpdotnet/Protocol/Messages/PaginatedResult.cs

@@ -0,0 +1,12 @@
+namespace McpDotNet.Protocol.Messages;
+
+/// <summary>
+/// A paginated result payload.
+/// </summary>
+public class PaginatedResult
+{
+    /// <summary>
+    /// An opaque token representing the pagination position after the last returned result.\nIf present, there may be more results available.
+    /// </summary>
+    public string? NextCursor { get; set; }
+}

src/mcpdotnet/Protocol/Types/BlobResourceContents.cs

@@ -18,4 +18,5 @@ public record BlobResourceContents : IResourceContents
     /// </summary>
     [JsonPropertyName("blob")]
     public required string Blob { get; init; }
-}
+}
+

src/mcpdotnet/Protocol/Types/CallToolResponse.cs

@@ -9,7 +9,7 @@ public class CallToolResponse
     /// <summary>
     /// The server's response to a tools/call request from the client.
     /// </summary>
-    public List<ToolContent> Content { get; set; } = new();
+    public List<Content> Content { get; set; } = new();
 
     /// <summary>
     /// Whether the tool call was unsuccessful. If true, the call was unsuccessful.

src/mcpdotnet/Protocol/Types/Content.cs

@@ -1,97 +1,58 @@
-// Protocol/Types/Content.cs
-namespace McpDotNet.Protocol.Types;
-
-using System.Text.Json.Serialization;
+namespace McpDotNet.Protocol.Types;
 
 /// <summary>
-/// Represents the type of role in the conversation.
+/// Represents the content of a tool response.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/schema.json">See the schema for details</see>
+/// There are multiple subtypes of content, depending on the "type" field, these are represented as separate classes.
 /// </summary>
-public enum Role
-{
-    [JsonPropertyName("user")]
-    User,
-
-    [JsonPropertyName("assistant")]
-    Assistant
-}
-
-/// <summary>
-/// Base interface for content types in messages.
-/// </summary>
-public interface IContent
-{
-    string Type { get; }
-    Annotations? Annotations { get; }
-}
-
-/// <summary>
-/// Represents text content in messages.
-/// </summary>
-public record TextContent : IContent
+public class Content
 {
     /// <summary>
-    /// The type of content. Always "text".
+    /// The type of content. This determines the structure of the content object. Can be "image", "text", "resource".
     /// </summary>
-    [JsonPropertyName("type")]
-    public string Type => "text";
+    public string Type { get; set; } = string.Empty;
 
     /// <summary>
     /// The text content of the message.
     /// </summary>
-    [JsonPropertyName("text")]
-    public required string Text { get; init; }
-
-    /// <summary>
-    /// Optional annotations for the content.
-    /// </summary>
-    [JsonPropertyName("annotations")]
-    public Annotations? Annotations { get; init; }
-}
-
-/// <summary>
-/// Represents image content in messages.
-/// </summary>
-public record ImageContent : IContent
-{
-    /// <summary>
-    /// The type of content. Always "image".
-    /// </summary>
-    [JsonPropertyName("type")]
-    public string Type => "image";
+    public string? Text { get; set; }
 
     /// <summary>
     /// The base64-encoded image data.
     /// </summary>
-    [JsonPropertyName("data")]
-    public required string Data { get; init; }
+    public string? Data { get; set; }
 
     /// <summary>
     /// The MIME type of the image.
     /// </summary>
-    [JsonPropertyName("mimeType")]
-    public required string MimeType { get; init; }
+    public string? MimeType { get; set; }
 
     /// <summary>
-    /// Optional annotations for the content.
+    /// One of BlobResourceContents or TextResourceContents.
     /// </summary>
-    [JsonPropertyName("annotations")]
-    public Annotations? Annotations { get; init; }
-}
-
-/// <summary>
-/// Represents annotations that can be attached to content.
-/// </summary>
-public record Annotations
-{
-    /// <summary>
-    /// Describes who the intended customer of this object or data is.
-    /// </summary>
-    [JsonPropertyName("audience")]
-    public Role[]? Audience { get; init; }
+    public object? Resource { get; set; }
 
     /// <summary>
-    /// Describes how important this data is for operating the server (0 to 1).
+    /// Validates the content object. 
     /// </summary>
-    [JsonPropertyName("priority")]
-    public float? Priority { get; init; }
-}
+    /// <returns>Whether the type of tool content has the correct data fields provided.</returns>
+    public bool Validate()
+    {
+        if (Type == "text")
+        {
+            return !string.IsNullOrEmpty(Text);
+        }
+        else if (Type == "image")
+        {
+            return !string.IsNullOrEmpty(Data) && !string.IsNullOrEmpty(MimeType);
+        }
+        else if (Type == "resource")
+        {
+            return Resource is BlobResourceContents || Resource is TextResourceContents;
+        }
+        else
+        {
+            return false;
+        }
+    }
+}

src/mcpdotnet/Protocol/Types/GetPromptResult.cs

@@ -0,0 +1,18 @@
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// The server's response to a prompts/get request from the client.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/schema.json">See the schema for details</see>
+/// </summary>
+public class GetPromptResult
+{
+    /// <summary>
+    /// An optional description for the prompt.
+    /// </summary>
+    public string? Description { get; set; }
+
+    /// <summary>
+    /// The prompt or prompt template that the server offers.
+    /// </summary>
+    public List<PromptMessage> Messages { get; set; } = new();
+}

src/mcpdotnet/Protocol/Types/IContent.cs

@@ -0,0 +1,97 @@
+// Protocol/Types/Content.cs
+namespace McpDotNet.Protocol.Types;
+
+using System.Text.Json.Serialization;
+
+/// <summary>
+/// Represents the type of role in the conversation.
+/// </summary>
+public enum Role
+{
+    [JsonPropertyName("user")]
+    User,
+
+    [JsonPropertyName("assistant")]
+    Assistant
+}
+
+/// <summary>
+/// Base interface for content types in messages.
+/// </summary>
+public interface IContent
+{
+    string Type { get; }
+    Annotations? Annotations { get; }
+}
+
+/// <summary>
+/// Represents text content in messages.
+/// </summary>
+public record TextContent : IContent
+{
+    /// <summary>
+    /// The type of content. Always "text".
+    /// </summary>
+    [JsonPropertyName("type")]
+    public string Type => "text";
+
+    /// <summary>
+    /// The text content of the message.
+    /// </summary>
+    [JsonPropertyName("text")]
+    public required string Text { get; init; }
+
+    /// <summary>
+    /// Optional annotations for the content.
+    /// </summary>
+    [JsonPropertyName("annotations")]
+    public Annotations? Annotations { get; init; }
+}
+
+/// <summary>
+/// Represents image content in messages.
+/// </summary>
+public record ImageContent : IContent
+{
+    /// <summary>
+    /// The type of content. Always "image".
+    /// </summary>
+    [JsonPropertyName("type")]
+    public string Type => "image";
+
+    /// <summary>
+    /// The base64-encoded image data.
+    /// </summary>
+    [JsonPropertyName("data")]
+    public required string Data { get; init; }
+
+    /// <summary>
+    /// The MIME type of the image.
+    /// </summary>
+    [JsonPropertyName("mimeType")]
+    public required string MimeType { get; init; }
+
+    /// <summary>
+    /// Optional annotations for the content.
+    /// </summary>
+    [JsonPropertyName("annotations")]
+    public Annotations? Annotations { get; init; }
+}
+
+/// <summary>
+/// Represents annotations that can be attached to content.
+/// </summary>
+public record Annotations
+{
+    /// <summary>
+    /// Describes who the intended customer of this object or data is.
+    /// </summary>
+    [JsonPropertyName("audience")]
+    public Role[]? Audience { get; init; }
+
+    /// <summary>
+    /// Describes how important this data is for operating the server (0 to 1).
+    /// </summary>
+    [JsonPropertyName("priority")]
+    public float? Priority { get; init; }
+}

src/mcpdotnet/Protocol/Types/ListPromptsResult.cs

@@ -0,0 +1,15 @@
+using McpDotNet.Protocol.Messages;
+
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// The server's response to a prompts/list request from the client.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/schema.json">See the schema for details</see>
+/// </summary>
+public class ListPromptsResult : PaginatedResult
+{
+    /// <summary>
+    /// A list of prompts or prompt templates that the server offers.
+    /// </summary>
+    public List<Prompt> Prompts { get; set; } = new();
+}

src/mcpdotnet/Protocol/Types/ListResourcesResult.cs

@@ -0,0 +1,15 @@
+using McpDotNet.Protocol.Messages;
+
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// The server's response to a resources/list request from the client.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/schema.json">See the schema for details</see>
+/// </summary>
+public class ListResourcesResult : PaginatedResult
+{
+    /// <summary>
+    /// A list of resources that the server offers.
+    /// </summary>
+    public List<Resource> Resources { get; set; } = new();
+}

src/mcpdotnet/Protocol/Types/ListToolsResult.cs

@@ -0,0 +1,15 @@
+using McpDotNet.Protocol.Messages;
+
+namespace McpDotNet.Protocol.Types;
+
+/// <summary>
+/// A response to a request to list the tools available on the server.
+/// <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/schema.json">See the schema for details</see>
+/// </summary>
+public class ListToolsResult : PaginatedResult
+{
+    /// <summary>
+    /// The server's response to a tools/list request from the client.
+    /// </summary>
+    public List<Tool> Tools { get; set; } = new();
+}