.NET: fix: align Anthropic Extensions AI version (microsoft#5709)

* fix: align Anthropic Extensions AI version

* test: update Anthropic test stubs for new interfaces

---------

Co-authored-by: Jacob Alber <jaalber@microsoft.com>

Author: danyalahmed1995

dotnet/Directory.Packages.props

@@ -11,7 +11,7 @@
   </PropertyGroup>
   <ItemGroup>
     <!-- Aspire.* -->
-    <PackageVersion Include="Anthropic" Version="12.13.0" />
+    <PackageVersion Include="Anthropic" Version="12.20.0" />
     <PackageVersion Include="Anthropic.Foundry" Version="0.5.0" />
     <PackageVersion Include="Aspire.Hosting" Version="$(AspireAppHostSdkVersion)" />
     <PackageVersion Include="Aspire.Azure.AI.OpenAI" Version="13.0.0-preview.1.25560.3" />
@@ -194,4 +194,4 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
   </ItemGroup>
-</Project>
+</Project>

dotnet/tests/AnthropicChatCompletion.IntegrationTests/AnthropicChatCompletionFixture.cs

@@ -102,11 +102,6 @@ public Task DeleteSessionAsync(AgentSession session) =>
 
     public async ValueTask InitializeAsync()
     {
-        // Temporarily disabled: Anthropic SDK has a binary incompatibility with the current
-        // Microsoft.Extensions.AI version (WebSearchToolResultContent.Results method not found).
-        // See: https://github.com/microsoft/agent-framework/pull/5515
-        Assert.Skip("Anthropic integration tests temporarily disabled due to SDK incompatibility with Microsoft.Extensions.AI");
-
         try
         {
             _ = TestConfiguration.GetRequiredValue(TestSettings.AnthropicApiKey);

dotnet/tests/AnthropicChatCompletion.IntegrationTests/AnthropicSkillsIntegrationTests.cs

@@ -18,11 +18,7 @@ namespace AnthropicChatCompletion.IntegrationTests;
 /// Integration tests for Anthropic Skills functionality.
 /// These tests are designed to be run locally with a valid Anthropic API key.
 /// </summary>
-/// <remarks>
-/// Temporarily disabled due to Anthropic SDK binary incompatibility with
-/// the current Microsoft.Extensions.AI version (WebSearchToolResultContent.Results).
-/// </remarks>
-[Trait("Category", "IntegrationDisabled")]
+[Trait("Category", "Integration")]
 public sealed class AnthropicSkillsIntegrationTests
 {
     [Fact]

dotnet/tests/Microsoft.Agents.AI.Anthropic.UnitTests/Extensions/AnthropicBetaServiceExtensionsTests.cs

@@ -442,6 +442,7 @@ public TestAnthropicChatClient()
         public TimeSpan? Timeout { get => throw new NotImplementedException(); init => throw new NotImplementedException(); }
         public string? ApiKey { get => throw new NotImplementedException(); init => throw new NotImplementedException(); }
         public string? AuthToken { get => throw new NotImplementedException(); init => throw new NotImplementedException(); }
+        public string? WebhookKey { get => throw new NotImplementedException(); init => throw new NotImplementedException(); }
 
         public IAnthropicClientWithRawResponse WithRawResponse => throw new NotImplementedException();
 
@@ -491,6 +492,12 @@ public TestBetaService(IAnthropicClient client)
 
             public global::Anthropic.Services.Beta.IVaultService Vaults => throw new NotImplementedException();
 
+            public global::Anthropic.Services.Beta.IMemoryStoreService MemoryStores => throw new NotImplementedException();
+
+            public global::Anthropic.Services.Beta.IWebhookService Webhooks => throw new NotImplementedException();
+
+            public global::Anthropic.Services.Beta.IUserProfileService UserProfiles => throw new NotImplementedException();
+
             public IBetaService WithOptions(Func<ClientOptions, ClientOptions> modifier)
             {
                 throw new NotImplementedException();

dotnet/tests/Microsoft.Agents.AI.Anthropic.UnitTests/Extensions/AnthropicClientExtensionsTests.cs

@@ -72,6 +72,7 @@ public TestAnthropicChatClient()
         public TimeSpan? Timeout { get => throw new NotImplementedException(); init => throw new NotImplementedException(); }
         public string? ApiKey { get => throw new NotImplementedException(); init => throw new NotImplementedException(); }
         public string? AuthToken { get => throw new NotImplementedException(); init => throw new NotImplementedException(); }
+        public string? WebhookKey { get => throw new NotImplementedException(); init => throw new NotImplementedException(); }
 
         public IAnthropicClientWithRawResponse WithRawResponse => throw new NotImplementedException();