Merge remote-tracking branch 'origin/main' into localden/experimental

Author: halter73

samples/AspNetCoreSseServer/Program.cs

@@ -2,12 +2,14 @@
 using OpenTelemetry.Metrics;
 using OpenTelemetry.Trace;
 using TestServerWithHosting.Tools;
+using TestServerWithHosting.Resources;
 
 var builder = WebApplication.CreateBuilder(args);
 builder.Services.AddMcpServer()
     .WithHttpTransport()
     .WithTools<EchoTool>()
-    .WithTools<SampleLlmTool>();
+    .WithTools<SampleLlmTool>()
+    .WithResources<SimpleResourceType>();
 
 builder.Services.AddOpenTelemetry()
     .WithTracing(b => b.AddSource("*")

samples/AspNetCoreSseServer/Resources/SimpleResourceType.cs

@@ -0,0 +1,12 @@
+using ModelContextProtocol.Protocol;
+using ModelContextProtocol.Server;
+using System.ComponentModel;
+
+namespace TestServerWithHosting.Resources;
+
+[McpServerResourceType]
+public class SimpleResourceType
+{
+    [McpServerResource, Description("A direct text resource")]
+    public static string DirectTextResource() => "This is a direct resource";
+}

samples/QuickstartClient/Program.cs

@@ -88,7 +88,7 @@ static void PromptForInput()
     {
         [var script] when script.EndsWith(".py") => ("python", args),
         [var script] when script.EndsWith(".js") => ("node", args),
-        [var script] when Directory.Exists(script) || (File.Exists(script) && script.EndsWith(".csproj")) => ("dotnet", ["run", "--project", script, "--no-build"]),
-        _ => ("dotnet", ["run", "--project", "../../../../QuickstartWeatherServer", "--no-build"])
+        [var script] when Directory.Exists(script) || (File.Exists(script) && script.EndsWith(".csproj")) => ("dotnet", ["run", "--project", script]),
+        _ => ("dotnet", ["run", "--project", "../QuickstartWeatherServer"])
     };
 }

src/Directory.Build.props

@@ -5,8 +5,8 @@
     <PackageProjectUrl>https://github.com/modelcontextprotocol/csharp-sdk</PackageProjectUrl>
     <RepositoryUrl>https://github.com/modelcontextprotocol/csharp-sdk</RepositoryUrl>
     <RepositoryType>git</RepositoryType>
-    <VersionPrefix>0.2.0</VersionPrefix>
-    <VersionSuffix>preview.4</VersionSuffix>
+    <VersionPrefix>0.3.0</VersionPrefix>
+    <VersionSuffix>preview.1</VersionSuffix>
     <Authors>ModelContextProtocolOfficial</Authors>
     <Copyright>© Anthropic and Contributors.</Copyright>
     <PackageTags>ModelContextProtocol;mcp;ai;llm</PackageTags>

src/ModelContextProtocol.AspNetCore/HttpServerTransportOptions.cs

@@ -6,7 +6,7 @@ namespace ModelContextProtocol.AspNetCore;
 /// <summary>
 /// Configuration options for <see cref="M:McpEndpointRouteBuilderExtensions.MapMcp"/>.
 /// which implements the Streaming HTTP transport for the Model Context Protocol.
-/// See the protocol specification for details on the Streamable HTTP transport. <see href="https://modelcontextprotocol.io/specification/2025-03-26/basic/transports#streamable-http"/>
+/// See the protocol specification for details on the Streamable HTTP transport. <see href="https://modelcontextprotocol.io/specification/2025-06-18/basic/transports#streamable-http"/>
 /// </summary>
 public class HttpServerTransportOptions
 {

src/ModelContextProtocol.AspNetCore/McpEndpointRouteBuilderExtensions.cs

@@ -15,7 +15,7 @@ public static class McpEndpointRouteBuilderExtensions
 {
     /// <summary>
     /// Sets up endpoints for handling MCP Streamable HTTP transport.
-    /// See <see href="https://modelcontextprotocol.io/specification/2025-03-26/basic/transports#streamable-http">the 2025-03-26 protocol specification</see> for details about the Streamable HTTP transport.
+    /// See <see href="https://modelcontextprotocol.io/specification/2025-06-18/basic/transports#streamable-http">the 2025-06-18 protocol specification</see> for details about the Streamable HTTP transport.
     /// Also maps legacy SSE endpoints for backward compatibility at the path "/sse" and "/message". <see href="https://modelcontextprotocol.io/specification/2024-11-05/basic/transports#http-with-sse">the 2024-11-05 protocol specification</see> for details about the HTTP with SSE transport.
     /// </summary>
     /// <param name="endpoints">The web application to attach MCP HTTP endpoints.</param>

src/ModelContextProtocol.Core/Client/McpClientTool.cs

@@ -77,6 +77,9 @@ internal McpClientTool(
     /// <inheritdoc/>
     public override JsonElement JsonSchema => ProtocolTool.InputSchema;
 
+    /// <inheritdoc/>
+    public override JsonElement? ReturnJsonSchema => ProtocolTool.OutputSchema;
+
     /// <inheritdoc/>
     public override JsonSerializerOptions JsonSerializerOptions { get; }
 

src/ModelContextProtocol.Core/Client/SseClientTransportOptions.cs

@@ -41,7 +41,7 @@ public required Uri Endpoint
     /// Streamable HTTP transport and automatically fall back to SSE transport if the server doesn't support it.
     /// </para>
     /// <para>
-    /// <see href="https://modelcontextprotocol.io/specification/2025-03-26/basic/transports#streamable-http">Streamable HTTP transport specification</see>.
+    /// <see href="https://modelcontextprotocol.io/specification/2025-06-18/basic/transports#streamable-http">Streamable HTTP transport specification</see>.
     /// <see href="https://modelcontextprotocol.io/specification/2024-11-05/basic/transports#http-with-sse">HTTP with SSE transport specification</see>.
     /// </para>
     /// </remarks>

src/ModelContextProtocol.Core/McpSession.cs

@@ -29,12 +29,13 @@ internal sealed partial class McpSession : IDisposable
         "mcp.server.operation.duration", "Measures the duration of inbound message processing.", longBuckets: false);
 
     /// <summary>The latest version of the protocol supported by this implementation.</summary>
-    internal const string LatestProtocolVersion = "2025-03-26";
+    internal const string LatestProtocolVersion = "2025-06-18";
 
     /// <summary>All protocol versions supported by this implementation.</summary>
     internal static readonly string[] SupportedProtocolVersions =
     [
         "2024-11-05",
+        "2025-03-26",
         LatestProtocolVersion,
     ];