Bump MCP SDK to 2.0.0-preview.3

Directory.Packages.props

@@ -89,8 +89,8 @@
     <PackageVersion Include="Microsoft.DataFactory.MCP.Core" Version="0.21.0-beta" />
     <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="10.0.2" />
     <PackageVersion Include="Microsoft.Extensions.Hosting" Version="10.0.2" />
-    <PackageVersion Include="ModelContextProtocol" Version="2.0.0-preview.1" />
-    <PackageVersion Include="ModelContextProtocol.AspNetCore" Version="2.0.0-preview.1" />
+    <PackageVersion Include="ModelContextProtocol" Version="2.0.0-preview.3" />
+    <PackageVersion Include="ModelContextProtocol.AspNetCore" Version="2.0.0-preview.3" />
     <PackageVersion Include="MySqlConnector" Version="2.4.0" />
     <PackageVersion Include="Npgsql" Version="10.0.1" />
     <PackageVersion Include="YamlDotNet" Version="16.3.0" />

core/Azure.Mcp.Core/tests/Azure.Mcp.Core.Tests/Client/MockClientTests.cs

@@ -16,7 +16,9 @@ private static McpServerOptions CreateOptions(McpServerHandlers? serverHandlers
     {
         return new McpServerOptions
         {
-            ProtocolVersion = "2024",
+            // Use a supported protocol version. preview.3 tightened validation and
+            // rejects bare '2024'; supported versions: 2024-11-05, 2025-11-25, 2026-07-28.
+            ProtocolVersion = "2025-11-25",
             InitializationTimeout = TimeSpan.FromSeconds(30),
             Handlers = serverHandlers ?? new(),
             ServerInfo = new Implementation { Name = "Azure MCP", Version = "1.0.0-beta" }
@@ -50,7 +52,7 @@ await Invoke_Request_To_Server(
                 Assert.NotNull(result);
                 Assert.Equal("Azure MCP", result.ServerInfo.Name);
                 Assert.Equal("1.0.0-beta", result.ServerInfo.Version);
-                Assert.Equal("2024", result.ProtocolVersion);
+                Assert.Equal("2025-11-25", result.ProtocolVersion);
             });
     }
 

core/Azure.Mcp.Core/tests/Azure.Mcp.Core.Tests/ClientToolTests.cs

@@ -112,7 +112,13 @@ public async Task Should_Error_When_Resources_Unsubscribe_Not_Supported()
     [Fact]
     public async Task Should_Not_Hang_On_Logging_SetLevel_Not_Supported()
     {
-        await Client.SetLoggingLevelAsync(LoggingLevel.Info, cancellationToken: TestContext.Current.CancellationToken);
+        // logging/setLevel was removed in MCP 2026-07-28 (SDK 2.0.0-preview.3).
+        // The method is no longer supported; per-request log level is now set via
+        // _meta/io.modelcontextprotocol/logLevel. The call should throw rather than hang.
+        var ex = await Assert.ThrowsAsync<McpProtocolException>(
+            async () => await Client.SetLoggingLevelAsync(LoggingLevel.Info,
+                cancellationToken: TestContext.Current.CancellationToken));
+        Assert.Contains("logging/setLevel", ex.Message, StringComparison.OrdinalIgnoreCase);
     }
 
     [Fact]

servers/Azure.Mcp.Server/changelog-entries/1784845074408.yaml

@@ -0,0 +1,4 @@
+changes:
+  - section: "Other Changes"
+    description: "Updated ModelContextProtocol packages to 2.0.0-preview.3."
+    subsection: "Dependency Updates"

servers/Azure.Mcp.Server/tests/Azure.Mcp.Server.Tests/Infrastructure/ConsolidatedModeTests.cs

@@ -2,12 +2,51 @@
 // Licensed under the MIT License.
 
 using System.Net;
+using System.Text.Json.Nodes;
 using Xunit;
 
 namespace Azure.Mcp.Server.Tests.Infrastructure;
 
 public class ConsolidatedModeTests
 {
+    private const string StatelessProtocolVersion = "2026-07-28";
+
+    /// <summary>
+    /// Builds a <see cref="StringContent"/> for a 2026-07-28 stateless JSON-RPC request
+    /// containing the required <c>_meta</c> envelope fields. Optional extra <c>_meta</c>
+    /// entries (e.g. W3C trace context) can be merged in via <paramref name="extraMeta"/>.
+    /// </summary>
+    private static StringContent CreateStateless2026RequestContent(
+        string method,
+        int id = 1,
+        JsonObject? extraMeta = null)
+    {
+        var meta = new JsonObject
+        {
+            ["io.modelcontextprotocol/protocolVersion"] = StatelessProtocolVersion,
+            ["io.modelcontextprotocol/clientInfo"] = new JsonObject { ["name"] = "test-client", ["version"] = "1.0" },
+            ["io.modelcontextprotocol/clientCapabilities"] = new JsonObject()
+        };
+
+        if (extraMeta != null)
+        {
+            foreach (var (key, value) in extraMeta)
+            {
+                meta[key] = value?.DeepClone();
+            }
+        }
+
+        var body = new JsonObject
+        {
+            ["jsonrpc"] = "2.0",
+            ["id"] = id,
+            ["method"] = method,
+            ["params"] = new JsonObject { ["_meta"] = meta }
+        };
+
+        return new StringContent(body.ToJsonString(), System.Text.Encoding.UTF8, "application/json");
+    }
+
     [Fact]
     public async Task ConsolidatedMode_HttpTransport_Should_List_Tools_On_Root_Endpoint()
     {
@@ -37,10 +76,10 @@ public async Task ConsolidatedMode_HttpTransport_Should_List_Tools_On_Root_Endpo
             using var client = new HttpClient();
             using var request = new HttpRequestMessage(HttpMethod.Post, $"http://127.0.0.1:{port}/")
             {
-                Content = new StringContent("{" + "\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/list\",\"params\":{}" + "}", System.Text.Encoding.UTF8, "application/json")
+                Content = CreateStateless2026RequestContent("tools/list")
             };
             request.Headers.TryAddWithoutValidation("Accept", "application/json, text/event-stream");
-            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", "2026-07-28");
+            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", StatelessProtocolVersion);
             request.Headers.TryAddWithoutValidation("Mcp-Method", "tools/list");
             request.Headers.TryAddWithoutValidation("Mcp-Name", "tools/list");
 
@@ -93,16 +132,17 @@ public async Task ConsolidatedMode_HttpTransport_Should_Accept_Meta_In_Request_P
             using var client = new HttpClient();
             using var request = new HttpRequestMessage(HttpMethod.Post, $"http://127.0.0.1:{port}/")
             {
-                Content = new StringContent(
-                    "{" +
-                    "\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/list\",\"params\":{\"_meta\":{\"traceparent\":\"00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01\",\"clientId\":\"phase2-hardening-test\"}}" +
-                    "}",
-                    System.Text.Encoding.UTF8,
-                    "application/json")
+                Content = CreateStateless2026RequestContent(
+                    "tools/list",
+                    extraMeta: new JsonObject
+                    {
+                        ["traceparent"] = "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01",
+                        ["clientId"] = "phase2-hardening-test"
+                    })
             };
 
             request.Headers.TryAddWithoutValidation("Accept", "application/json, text/event-stream");
-            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", "2026-07-28");
+            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", StatelessProtocolVersion);
             request.Headers.TryAddWithoutValidation("Mcp-Method", "tools/list");
             request.Headers.TryAddWithoutValidation("Mcp-Name", "tools/list");
 
@@ -152,16 +192,11 @@ public async Task ConsolidatedMode_HttpTransport_Should_Support_ServerDiscover_W
             using var client = new HttpClient();
             using var request = new HttpRequestMessage(HttpMethod.Post, $"http://127.0.0.1:{port}/")
             {
-                Content = new StringContent(
-                    "{" +
-                    "\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"server/discover\",\"params\":{}" +
-                    "}",
-                    System.Text.Encoding.UTF8,
-                    "application/json")
+                Content = CreateStateless2026RequestContent("server/discover")
             };
 
             request.Headers.TryAddWithoutValidation("Accept", "application/json, text/event-stream");
-            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", "2026-07-28");
+            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", StatelessProtocolVersion);
             request.Headers.TryAddWithoutValidation("Mcp-Method", "server/discover");
             request.Headers.TryAddWithoutValidation("Mcp-Name", "server/discover");
 
@@ -213,10 +248,10 @@ public async Task ConsolidatedMode_HttpTransport_Should_Handle_Repeated_ToolsLis
 
             using var request1 = new HttpRequestMessage(HttpMethod.Post, $"http://127.0.0.1:{port}/")
             {
-                Content = new StringContent("{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/list\",\"params\":{}}", System.Text.Encoding.UTF8, "application/json")
+                Content = CreateStateless2026RequestContent("tools/list", id: 1)
             };
             request1.Headers.TryAddWithoutValidation("Accept", "application/json, text/event-stream");
-            request1.Headers.TryAddWithoutValidation("MCP-Protocol-Version", "2026-07-28");
+            request1.Headers.TryAddWithoutValidation("MCP-Protocol-Version", StatelessProtocolVersion);
             request1.Headers.TryAddWithoutValidation("Mcp-Method", "tools/list");
             request1.Headers.TryAddWithoutValidation("Mcp-Name", "tools/list");
 
@@ -225,10 +260,10 @@ public async Task ConsolidatedMode_HttpTransport_Should_Handle_Repeated_ToolsLis
 
             using var request2 = new HttpRequestMessage(HttpMethod.Post, $"http://127.0.0.1:{port}/")
             {
-                Content = new StringContent("{\"jsonrpc\":\"2.0\",\"id\":2,\"method\":\"tools/list\",\"params\":{}}", System.Text.Encoding.UTF8, "application/json")
+                Content = CreateStateless2026RequestContent("tools/list", id: 2)
             };
             request2.Headers.TryAddWithoutValidation("Accept", "application/json, text/event-stream");
-            request2.Headers.TryAddWithoutValidation("MCP-Protocol-Version", "2026-07-28");
+            request2.Headers.TryAddWithoutValidation("MCP-Protocol-Version", StatelessProtocolVersion);
             request2.Headers.TryAddWithoutValidation("Mcp-Method", "tools/list");
             request2.Headers.TryAddWithoutValidation("Mcp-Name", "tools/list");
 
@@ -341,22 +376,18 @@ public async Task ConsolidatedMode_HttpTransport_Should_Propagate_W3C_Trace_Cont
             using var client = new HttpClient();
             using var request = new HttpRequestMessage(HttpMethod.Post, $"http://127.0.0.1:{port}/")
             {
-                Content = new StringContent(
-                    "{" +
-                    "\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/list\",\"params\":{" +
-                    "\"_meta\":{" +
-                    "\"traceparent\":\"00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01\"," +
-                    "\"tracestate\":\"vendor1=opaquevalue1,vendor2=opaquevalue2\"," +
-                    "\"baggage\":\"userId=alice,serverNode=DF:28,isProduction=false\"" +
-                    "}" +
-                    "}" +
-                    "}",
-                    System.Text.Encoding.UTF8,
-                    "application/json")
+                Content = CreateStateless2026RequestContent(
+                    "tools/list",
+                    extraMeta: new JsonObject
+                    {
+                        ["traceparent"] = "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01",
+                        ["tracestate"] = "vendor1=opaquevalue1,vendor2=opaquevalue2",
+                        ["baggage"] = "userId=alice,serverNode=DF:28,isProduction=false"
+                    })
             };
 
             request.Headers.TryAddWithoutValidation("Accept", "application/json, text/event-stream");
-            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", "2026-07-28");
+            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", StatelessProtocolVersion);
             request.Headers.TryAddWithoutValidation("Mcp-Method", "tools/list");
             request.Headers.TryAddWithoutValidation("Mcp-Name", "tools/list");
 
@@ -634,10 +665,10 @@ public async Task ConsolidatedMode_HttpTransport_Should_Accept_NonNamedMethod_Wi
             using var client = new HttpClient();
             using var request = new HttpRequestMessage(HttpMethod.Post, $"http://127.0.0.1:{port}/")
             {
-                Content = new StringContent("{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/list\",\"params\":{}}", System.Text.Encoding.UTF8, "application/json")
+                Content = CreateStateless2026RequestContent("tools/list")
             };
             request.Headers.TryAddWithoutValidation("Accept", "application/json, text/event-stream");
-            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", "2026-07-28");
+            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", StatelessProtocolVersion);
             request.Headers.TryAddWithoutValidation("Mcp-Method", "tools/list");
             // Intentionally omit Mcp-Name — valid for a non-named method
 

servers/Azure.Mcp.Server/tests/Azure.Mcp.Server.Tests/Infrastructure/ServerModeCoverageTests.cs

@@ -115,6 +115,7 @@ public async Task NamespaceMode_Should_List_Tools_Without_Initialize()
     public async Task AllMode_Should_List_Tools_Without_Initialize()
     {
         // "all" mode exposes every individual Azure tool directly.
+        // Uses a longer timeout because registering all tools takes more time on slow CI runners.
         Assert.True(File.Exists(AzmcpPath), $"Executable not found at {AzmcpPath}. Please build the Azure.Mcp.Server project first.");
 
         var processStartInfo = new System.Diagnostics.ProcessStartInfo
@@ -141,7 +142,8 @@ public async Task AllMode_Should_List_Tools_Without_Initialize()
             await process.StandardInput.WriteLineAsync(listToolsRequest);
             await process.StandardInput.FlushAsync(TestContext.Current.CancellationToken);
 
-            var response = await ReadResponseAsync(process.StandardOutput);
+            // Allow up to 60 s: "all" mode registers every tool and is slower on macOS CI runners.
+            var response = await ReadResponseAsync(process.StandardOutput, TimeSpan.FromSeconds(60));
 
             Assert.NotNull(response);
             Assert.Contains("\"result\"", response, StringComparison.OrdinalIgnoreCase);
@@ -156,9 +158,9 @@ public async Task AllMode_Should_List_Tools_Without_Initialize()
         }
     }
 
-    private static async Task<string?> ReadResponseAsync(StreamReader reader)
+    private static async Task<string?> ReadResponseAsync(StreamReader reader, TimeSpan? timeout = null)
     {
-        using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(15));
+        using var cts = new CancellationTokenSource(timeout ?? TimeSpan.FromSeconds(15));
         try
         {
             return await reader.ReadLineAsync(cts.Token);

servers/Fabric.Mcp.Server/tests/Fabric.Mcp.Server.Tests/Infrastructure/ServerStartupTests.cs

@@ -2,12 +2,39 @@
 // Licensed under the MIT License.
 
 using System.Net;
+using System.Text.Json.Nodes;
 using Xunit;
 
 namespace Fabric.Mcp.Server.Tests.Infrastructure;
 
 public class ServerStartupTests
 {
+    private const string StatelessProtocolVersion = "2026-07-28";
+
+    /// <summary>
+    /// Builds a <see cref="StringContent"/> for a 2026-07-28 stateless JSON-RPC request
+    /// containing the required <c>_meta</c> envelope fields.
+    /// </summary>
+    private static StringContent CreateStateless2026RequestContent(string method, int id = 1)
+    {
+        var body = new JsonObject
+        {
+            ["jsonrpc"] = "2.0",
+            ["id"] = id,
+            ["method"] = method,
+            ["params"] = new JsonObject
+            {
+                ["_meta"] = new JsonObject
+                {
+                    ["io.modelcontextprotocol/protocolVersion"] = StatelessProtocolVersion,
+                    ["io.modelcontextprotocol/clientInfo"] = new JsonObject { ["name"] = "test-client", ["version"] = "1.0" },
+                    ["io.modelcontextprotocol/clientCapabilities"] = new JsonObject()
+                }
+            }
+        };
+        return new StringContent(body.ToJsonString(), System.Text.Encoding.UTF8, "application/json");
+    }
+
     [Fact]
     public async Task Server_Should_List_Tools_Over_Http_Root_Endpoint()
     {
@@ -47,10 +74,10 @@ public async Task Server_Should_List_Tools_Over_Http_Root_Endpoint()
             using var client = new HttpClient();
             using var request = new HttpRequestMessage(HttpMethod.Post, $"http://127.0.0.1:{port}/")
             {
-                Content = new StringContent("{" + "\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/list\",\"params\":{}" + "}", System.Text.Encoding.UTF8, "application/json")
+                Content = CreateStateless2026RequestContent("tools/list")
             };
             request.Headers.TryAddWithoutValidation("Accept", "application/json, text/event-stream");
-            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", "2026-07-28");
+            request.Headers.TryAddWithoutValidation("MCP-Protocol-Version", StatelessProtocolVersion);
             request.Headers.TryAddWithoutValidation("Mcp-Method", "tools/list");
             request.Headers.TryAddWithoutValidation("Mcp-Name", "tools/list");