diff --git a/.github/workflows/ci-build-test.yml b/.github/workflows/ci-build-test.yml
index 9a66ccd..5e4b223 100644
--- a/.github/workflows/ci-build-test.yml
+++ b/.github/workflows/ci-build-test.yml
@@ -50,6 +50,10 @@ jobs:
       if: runner.os == 'Linux'
       run: sudo apt-get install -y mono-devel
 
+    - name: Setup Mono on macOS
+      if: runner.os == 'macOS'
+      run: brew install mono
+
     - name: Set up Node.js
       uses: actions/setup-node@cdca7365b2dadb8aad0a33bc7601856ffabcc48e # v4.3.0
       with:
diff --git a/Directory.Build.props b/Directory.Build.props
index bca3759..b0cf7f2 100644
--- a/Directory.Build.props
+++ b/Directory.Build.props
@@ -34,4 +34,9 @@
   <PropertyGroup Condition="'$(GITHUB_ACTIONS)' == 'true'">
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>
+
+  <PropertyGroup Condition="$(TargetFramework.StartsWith('net4'))">
+    <!-- Don't use x64 when running netfx test procs on Windows ARM -->
+    <PreferNativeArm64>true</PreferNativeArm64>
+  </PropertyGroup>
 </Project>
diff --git a/Directory.Packages.props b/Directory.Packages.props
index 6da9521..27431dd 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -3,7 +3,7 @@
     <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
     <System9Version>9.0.5</System9Version>
     <System10Version>10.0.0-preview.4.25258.110</System10Version>
-    <MicrosoftExtensionsAIVersion>9.7.1</MicrosoftExtensionsAIVersion>
+    <MicrosoftExtensionsAIVersion>9.8.0</MicrosoftExtensionsAIVersion>
   </PropertyGroup>
 
   <!-- Product dependencies netstandard -->
@@ -47,13 +47,13 @@
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
 
     <!-- Testing dependencies -->
-    <PackageVersion Include="Anthropic.SDK" Version="5.4.1" />
+    <PackageVersion Include="Anthropic.SDK" Version="5.5.1" />
     <PackageVersion Include="coverlet.collector" Version="6.0.4">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageVersion>
     <PackageVersion Include="GitHubActionsTestLogger" Version="2.4.1" />
-    <PackageVersion Include="Microsoft.Extensions.AI.OpenAI" Version="9.7.0-preview.1.25356.2" />
+    <PackageVersion Include="Microsoft.Extensions.AI.OpenAI" Version="9.8.0-preview.1.25412.6" />
     <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="$(System9Version)" />
     <PackageVersion Include="Microsoft.Extensions.Hosting" Version="$(System9Version)" />
     <PackageVersion Include="Microsoft.Extensions.Logging" Version="$(System9Version)" />
@@ -66,8 +66,8 @@
     <PackageVersion Include="OpenTelemetry.Exporter.InMemory" Version="1.12.0" />
     <PackageVersion Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.12.0" />
     <PackageVersion Include="OpenTelemetry.Instrumentation.Http" Version="1.12.0" />
-    <PackageVersion Include="OpenTelemetry.Extensions.Hosting" Version="1.12.0"  />
-    <PackageVersion Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.12.0"  />
+    <PackageVersion Include="OpenTelemetry.Extensions.Hosting" Version="1.12.0" />
+    <PackageVersion Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.12.0" />
     <PackageVersion Include="Serilog.Extensions.Hosting" Version="9.0.0" />
     <PackageVersion Include="Serilog.Extensions.Logging" Version="9.0.1" />
     <PackageVersion Include="Serilog.Sinks.Console" Version="6.0.0" />
@@ -75,9 +75,9 @@
     <PackageVersion Include="Serilog.Sinks.File" Version="7.0.0" />
     <PackageVersion Include="Serilog" Version="4.3.0" />
     <PackageVersion Include="System.Linq.AsyncEnumerable" Version="$(System10Version)" />
-    <PackageVersion Include="xunit.v3" Version="2.0.3" />
-    <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.1" />
+    <PackageVersion Include="xunit.v3" Version="3.0.1" />
+    <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.4" />
     <PackageVersion Include="System.Net.Http" Version="4.3.4" />
-    <PackageVersion Include="JsonSchema.Net" Version="7.3.4" />
+    <PackageVersion Include="JsonSchema.Net" Version="7.4.0" />
   </ItemGroup>
 </Project>
\ No newline at end of file
diff --git a/tests/ModelContextProtocol.Tests/Transport/StdioClientTransportTests.cs b/tests/ModelContextProtocol.Tests/Transport/StdioClientTransportTests.cs
index 93cbcec..dfde342 100644
--- a/tests/ModelContextProtocol.Tests/Transport/StdioClientTransportTests.cs
+++ b/tests/ModelContextProtocol.Tests/Transport/StdioClientTransportTests.cs
@@ -19,7 +19,10 @@ public class StdioClientTransportTests(ITestOutputHelper testOutputHelper) : Log
             new(new() { Command = "ls", Arguments = [id] }, LoggerFactory);
 
         IOException e = await Assert.ThrowsAsync<IOException>(() => McpClientFactory.CreateAsync(transport, loggerFactory: LoggerFactory, cancellationToken: TestContext.Current.CancellationToken));
-        Assert.Contains(id, e.ToString());
+        if (!RuntimeInformation.IsOSPlatform(OSPlatform.OSX))
+        {
+            Assert.Contains(id, e.ToString());
+        }
     }
     
     [Fact(Skip = "Platform not supported by this test.", SkipUnless = nameof(IsStdErrCallbackSupported))]