diff --git a/Directory.Packages.props b/Directory.Packages.props
index b5f33da..3160c83 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -6,15 +6,15 @@
     <PackageVersion Include="coverlet.collector" Version="10.1.0"/>
     <PackageVersion Include="FluentAssertions" Version="8.11.0"/>
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="5.9.0"/>
-    <PackageVersion Include="Microsoft.CodeAnalysis.NetAnalyzers" Version="10.0.401"/>
-    <PackageVersion Include="Microsoft.EntityFrameworkCore" Version="10.0.12"/>
+    <PackageVersion Include="Microsoft.CodeAnalysis.NetAnalyzers" Version="10.0.402"/>
+    <PackageVersion Include="Microsoft.EntityFrameworkCore" Version="10.0.13"/>
     <PackageVersion Include="Microsoft.EntityFrameworkCore.Design" Version="10.0.9"/>
-    <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="10.0.12"/>
-    <PackageVersion Include="Microsoft.Extensions.Hosting" Version="10.0.12"/>
-    <PackageVersion Include="Microsoft.Extensions.Logging.Abstractions" Version="10.0.12"/>
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.10.1"/>
+    <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="10.0.13"/>
+    <PackageVersion Include="Microsoft.Extensions.Hosting" Version="10.0.13"/>
+    <PackageVersion Include="Microsoft.Extensions.Logging.Abstractions" Version="10.0.13"/>
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.11.0"/>
     <PackageVersion Include="Microsoft.VisualStudio.SolutionPersistence" Version="1.0.52"/>
-    <PackageVersion Include="Microsoft.VisualStudio.Threading.Analyzers" Version="18.7.23"/>
+    <PackageVersion Include="Microsoft.VisualStudio.Threading.Analyzers" Version="18.12.1"/>
     <PackageVersion Include="NSubstitute" Version="6.2.0"/>
     <PackageVersion Include="ModelContextProtocol" Version="2.2.0"/>
     <PackageVersion Include="Roslynator.Analyzers" Version="5.0.1"/>
@@ -24,6 +24,6 @@
     <PackageVersion Include="Spectre.Console.Cli" Version="0.57.2"/>
     <PackageVersion Include="Spectre.Console.Testing" Version="0.57.2"/>
     <PackageVersion Include="xunit" Version="2.9.3"/>
-    <PackageVersion Include="xunit.runner.visualstudio" Version="4.0.0"/>
+    <PackageVersion Include="xunit.runner.visualstudio" Version="4.0.1"/>
   </ItemGroup>
 </Project>
\ No newline at end of file
diff --git a/tests/ProjGraph.Tests.Integration.Mcp/Helpers/InProcessMcpSession.cs b/tests/ProjGraph.Tests.Integration.Mcp/Helpers/InProcessMcpSession.cs
index 039d611..aced357 100644
--- a/tests/ProjGraph.Tests.Integration.Mcp/Helpers/InProcessMcpSession.cs
+++ b/tests/ProjGraph.Tests.Integration.Mcp/Helpers/InProcessMcpSession.cs
@@ -86,8 +86,11 @@ public static McpServerOptions CreateServerOptions()
     /// When <see langword="true"/> (the default), pins the client to the <c>2025-11-25</c>
     /// handshake so client capabilities are established session-scoped on the root
     /// <see cref="McpServer"/> — required by tests that drive that root instance directly. When
-    /// <see langword="false"/>, the client negotiates the latest revision, where capabilities
-    /// arrive per request in <c>_meta</c> and are visible only on the request-scoped server.
+    /// <see langword="false"/>, pins the client to <c>2026-07-28</c>, where capabilities arrive
+    /// per request in <c>_meta</c> and are visible only on the request-scoped server. Pinning
+    /// matters: left unset, the client falls back to the <c>initialize</c> handshake whenever its
+    /// <c>server/discover</c> probe outlasts <see cref="McpClientOptions.DiscoverProbeTimeout"/>
+    /// (5 seconds), which a loaded CI runner can hit, silently testing the wrong revision.
     /// </param>
     public static McpClientOptions CreateClientOptionsWithRoots(
         Func<IReadOnlyList<string>> rootProvider,
@@ -98,7 +101,10 @@ public static McpClientOptions CreateClientOptionsWithRoots(
 #pragma warning disable MCP9005
         return new McpClientOptions
         {
-            ProtocolVersion = pinDownLevel ? "2025-11-25" : null,
+            ProtocolVersion = pinDownLevel ? "2025-11-25" : "2026-07-28",
+            // The probe is only issued on 2026-07-28; leave it bounded by InitializationTimeout
+            // alone so a slow runner does not fail the connection.
+            DiscoverProbeTimeout = Timeout.InfiniteTimeSpan,
             ClientInfo = new Implementation
             {
                 Name = "ProjGraph.Tests",
diff --git a/tests/ProjGraph.Tests.Integration.Mcp/McpToolRootsTests.cs b/tests/ProjGraph.Tests.Integration.Mcp/McpToolRootsTests.cs
index 6a9cd1d..1909d5a 100644
--- a/tests/ProjGraph.Tests.Integration.Mcp/McpToolRootsTests.cs
+++ b/tests/ProjGraph.Tests.Integration.Mcp/McpToolRootsTests.cs
@@ -49,8 +49,8 @@ public async Task CallTool_RelativePath_OnCurrentProtocol_ShouldResolveAgainstTh
 
         await using var session = await InProcessMcpSession.StartAsync(
             CreateServerOptionsWithTools(),
-            // Not pinned: the client negotiates the latest revision (2026-07-28), which drops the
-            // initialize handshake. This is the case that silently regressed on the v2 upgrade.
+            // Pinned to the latest revision (2026-07-28), which drops the initialize handshake.
+            // This is the case that silently regressed on the v2 upgrade.
             InProcessMcpSession.CreateClientOptionsWithRoots(() => [_temp.DirectoryPath], pinDownLevel: false));
 
         var result = await session.Client.CallToolAsync(