Update Microsoft.Extensions.AI version & expose JSON configuration on McpServerResourceCreateOptions (#511)

sbomer · eiriktsarpalis · web-flow · commit 28d65470f445 · 2025-06-13T13:50:14.000+01:00
* Update Microsoft.Extensions.AI version

* Update Microsoft.Extensions.AI.OpenAI

* Fix failing tests; add JSON configuration options to McpServerResourceCreateOptions.

* Replace temporary code with `AIFunction.ReturnJsonSchema`

---------

Co-authored-by: Eirik Tsarpalis &lt;eirik.tsarpalis@gmail.com&gt;
diff --git 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>9.5.0</MicrosoftExtensionsAIVersion>
+    <MicrosoftExtensionsAIVersion>9.6.0</MicrosoftExtensionsAIVersion>
   </PropertyGroup>
 
   <!-- Product dependencies netstandard -->
@@ -50,7 +50,7 @@
       <PrivateAssets>all</PrivateAssets>
     </PackageVersion>
     <PackageVersion Include="GitHubActionsTestLogger" Version="2.4.1" />
-    <PackageVersion Include="Microsoft.Extensions.AI.OpenAI" Version="9.5.0-preview.1.25265.7" />
+    <PackageVersion Include="Microsoft.Extensions.AI.OpenAI" Version="9.6.0-preview.1.25310.2" />
     <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="$(System9Version)" />
     <PackageVersion Include="Microsoft.Extensions.Hosting" Version="$(System9Version)" />
     <PackageVersion Include="Microsoft.Extensions.Logging" Version="$(System9Version)" />
diff --git a/src/ModelContextProtocol.Core/McpJsonUtilities.cs b/src/ModelContextProtocol.Core/McpJsonUtilities.cs
@@ -85,30 +85,6 @@ internal static bool IsValidMcpToolSchema(JsonElement element)
         return false; // No type keyword found.
     }
 
-    internal static JsonElement? GetReturnSchema(this AIFunction function, AIJsonSchemaCreateOptions? schemaCreateOptions)
-    {
-        // TODO replace with https://github.com/dotnet/extensions/pull/6447 once merged.
-        if (function.UnderlyingMethod?.ReturnType is not Type returnType)
-        {
-            return null;
-        }
-
-        if (returnType == typeof(void) || returnType == typeof(Task) || returnType == typeof(ValueTask))
-        {
-            // Do not report an output schema for void or Task methods.
-            return null;
-        }
-
-        if (returnType.IsGenericType && returnType.GetGenericTypeDefinition() is Type genericTypeDef &&
-            (genericTypeDef == typeof(Task<>) || genericTypeDef == typeof(ValueTask<>)))
-        {
-            // Extract the real type from Task<T> or ValueTask<T> if applicable.
-            returnType = returnType.GetGenericArguments()[0];
-        }
-
-        return AIJsonUtilities.CreateJsonSchema(returnType, serializerOptions: function.JsonSerializerOptions, inferenceOptions: schemaCreateOptions);
-    }
-
     // Keep in sync with CreateDefaultOptions above.
     [JsonSourceGenerationOptions(JsonSerializerDefaults.Web,
         DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull,
@@ -157,6 +133,7 @@ internal static bool IsValidMcpToolSchema(JsonElement element)
     [JsonSerializable(typeof(SubscribeRequestParams))]
     [JsonSerializable(typeof(UnsubscribeRequestParams))]
     [JsonSerializable(typeof(IReadOnlyDictionary<string, object>))]
+    [JsonSerializable(typeof(PromptMessage[]))]
 
     // Primitive types for use in consuming AIFunctions
     [JsonSerializable(typeof(string))]
diff --git a/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerPrompt.cs b/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerPrompt.cs
@@ -71,6 +71,7 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(
             Description = options?.Description,
             MarshalResult = static (result, _, cancellationToken) => new ValueTask<object?>(result),
             SerializerOptions = options?.SerializerOptions ?? McpJsonUtilities.DefaultOptions,
+            JsonSchemaCreateOptions = options?.SchemaCreateOptions,
             ConfigureParameterBinding = pi =>
             {
                 if (pi.ParameterType == typeof(RequestContext<GetPromptRequestParams>))
@@ -151,7 +152,6 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(
                     return null;
                 }
             },
-            JsonSchemaCreateOptions = options?.SchemaCreateOptions,
         };
 
     /// <summary>Creates an <see cref="McpServerPrompt"/> that wraps the specified <see cref="AIFunction"/>.</summary>
diff --git a/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerResource.cs b/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerResource.cs
@@ -77,7 +77,8 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(
             Name = options?.Name ?? method.GetCustomAttribute<McpServerResourceAttribute>()?.Name,
             Description = options?.Description,
             MarshalResult = static (result, _, cancellationToken) => new ValueTask<object?>(result),
-            SerializerOptions = McpJsonUtilities.DefaultOptions,
+            SerializerOptions = options?.SerializerOptions ?? McpJsonUtilities.DefaultOptions,
+            JsonSchemaCreateOptions = options?.SchemaCreateOptions,
             ConfigureParameterBinding = pi =>
             {
                 if (pi.ParameterType == typeof(RequestContext<ReadResourceRequestParams>))
diff --git a/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerTool.cs b/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerTool.cs
@@ -86,6 +86,7 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(
             Description = options?.Description,
             MarshalResult = static (result, _, cancellationToken) => new ValueTask<object?>(result),
             SerializerOptions = options?.SerializerOptions ?? McpJsonUtilities.DefaultOptions,
+            JsonSchemaCreateOptions = options?.SchemaCreateOptions,
             ConfigureParameterBinding = pi =>
             {
                 if (pi.ParameterType == typeof(RequestContext<CallToolRequestParams>))
@@ -166,7 +167,6 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(
                     return null;
                 }
             },
-            JsonSchemaCreateOptions = options?.SchemaCreateOptions,
         };
 
     /// <summary>Creates an <see cref="McpServerTool"/> that wraps the specified <see cref="AIFunction"/>.</summary>
@@ -366,7 +366,7 @@ public override async ValueTask<CallToolResponse> InvokeAsync(
             return null;
         }
 
-        if (function.GetReturnSchema(toolCreateOptions?.SchemaCreateOptions) is not JsonElement outputSchema)
+        if (function.ReturnJsonSchema is not JsonElement outputSchema)
         {
             return null;
         }
diff --git a/src/ModelContextProtocol.Core/Server/McpServerResourceCreateOptions.cs b/src/ModelContextProtocol.Core/Server/McpServerResourceCreateOptions.cs
@@ -1,4 +1,6 @@
+using Microsoft.Extensions.AI;
 using System.ComponentModel;
+using System.Text.Json;
 
 namespace ModelContextProtocol.Server;
 
@@ -60,6 +62,22 @@ public sealed class McpServerResourceCreateOptions
     /// </summary>
     public string? MimeType { get; set; }
 
+    /// <summary>
+    /// Gets or sets the JSON serializer options to use when marshalling data to/from JSON.
+    /// </summary>
+    /// <remarks>
+    /// Defaults to <see cref="McpJsonUtilities.DefaultOptions"/> if left unspecified.
+    /// </remarks>
+    public JsonSerializerOptions? SerializerOptions { get; set; }
+
+    /// <summary>
+    /// Gets or sets the JSON schema options when creating <see cref="AIFunction"/> from a method.
+    /// </summary>
+    /// <remarks>
+    /// Defaults to <see cref="AIJsonSchemaCreateOptions.Default"/> if left unspecified.
+    /// </remarks>
+    public AIJsonSchemaCreateOptions? SchemaCreateOptions { get; set; }
+
     /// <summary>
     /// Creates a shallow clone of the current <see cref="McpServerResourceCreateOptions"/> instance.
     /// </summary>
@@ -71,5 +89,7 @@ internal McpServerResourceCreateOptions Clone() =>
             Name = Name,
             Description = Description,
             MimeType = MimeType,
+            SerializerOptions = SerializerOptions,
+            SchemaCreateOptions = SchemaCreateOptions,
         };
 }
diff --git a/tests/ModelContextProtocol.Tests/Server/McpServerPromptTests.cs b/tests/ModelContextProtocol.Tests/Server/McpServerPromptTests.cs
@@ -5,6 +5,8 @@
 using Moq;
 using System.ComponentModel;
 using System.Reflection;
+using System.Text.Json;
+using System.Text.Json.Nodes;
 
 namespace ModelContextProtocol.Tests.Server;
 
@@ -324,6 +326,11 @@ public async Task SupportsSchemaCreateOptions()
         {
             TransformSchemaNode = (context, node) =>
             {
+                if (node.GetValueKind() is not JsonValueKind.Object)
+                {
+                    node = new JsonObject();
+                }
+
                 node["description"] = "1234";
                 return node;
             }
diff --git a/tests/ModelContextProtocol.Tests/Server/McpServerResourceTests.cs b/tests/ModelContextProtocol.Tests/Server/McpServerResourceTests.cs
@@ -451,7 +451,7 @@ public async Task CanReturnResourceContents()
         {
             Assert.Same(mockServer.Object, server);
             return new TextResourceContents() { Text = "hello" };
-        }, new() { Name = "Test" });
+        }, new() { Name = "Test", SerializerOptions = JsonContext6.Default.Options });
         var result = await resource.ReadAsync(
             new RequestContext<ReadResourceRequestParams>(mockServer.Object) { Params = new() { Uri = "resource://Test" } },
             TestContext.Current.CancellationToken);
@@ -507,7 +507,7 @@ public async Task CanReturnCollectionOfStrings()
         {
             Assert.Same(mockServer.Object, server);
             return new List<string>() { "42", "43" };
-        }, new() { Name = "Test" });
+        }, new() { Name = "Test", SerializerOptions = JsonContext6.Default.Options });
         var result = await resource.ReadAsync(
             new RequestContext<ReadResourceRequestParams>(mockServer.Object) { Params = new() { Uri = "resource://Test" } },
             TestContext.Current.CancellationToken);
@@ -547,7 +547,7 @@ public async Task CanReturnCollectionOfAIContent()
                 new TextContent("hello!"),
                 new DataContent(new byte[] { 4, 5, 6 }, "application/json"),
             };
-        }, new() { Name = "Test" });
+        }, new() { Name = "Test", SerializerOptions = JsonContext6.Default.Options });
         var result = await resource.ReadAsync(
             new RequestContext<ReadResourceRequestParams>(mockServer.Object) { Params = new() { Uri = "resource://Test" } },
             TestContext.Current.CancellationToken);
@@ -575,5 +575,8 @@ private class DisposableResourceType : IDisposable
 
     [JsonSourceGenerationOptions(PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase)]
     [JsonSerializable(typeof(DisposableResourceType))]
+    [JsonSerializable(typeof(List<AIContent>))]
+    [JsonSerializable(typeof(List<string>))]
+    [JsonSerializable(typeof(TextResourceContents))]
     partial class JsonContext6 : JsonSerializerContext;
 }
diff --git a/tests/ModelContextProtocol.Tests/Server/McpServerToolTests.cs b/tests/ModelContextProtocol.Tests/Server/McpServerToolTests.cs
@@ -190,7 +190,7 @@ public async Task CanReturnCollectionOfAIContent()
                 new DataContent("data:image/png;base64,1234"),
                 new DataContent("data:audio/wav;base64,1234")
             };
-        });
+        }, new() { SerializerOptions = JsonContext2.Default.Options });
 
         var result = await tool.InvokeAsync(
             new RequestContext<CallToolRequestParams>(mockServer.Object),
@@ -288,7 +288,7 @@ public async Task CanReturnCollectionOfStrings()
         {
             Assert.Same(mockServer.Object, server);
             return new List<string>() { "42", "43" };
-        });
+        }, new() { SerializerOptions = JsonContext2.Default.Options });
         var result = await tool.InvokeAsync(
             new RequestContext<CallToolRequestParams>(mockServer.Object),
             TestContext.Current.CancellationToken);
@@ -632,5 +632,7 @@ record Person(string Name, int Age);
     [JsonSerializable(typeof(AsyncDisposableToolType))]
     [JsonSerializable(typeof(AsyncDisposableAndDisposableToolType))]
     [JsonSerializable(typeof(JsonSchema))]
+    [JsonSerializable(typeof(List<AIContent>))]
+    [JsonSerializable(typeof(List<string>))]
     partial class JsonContext2 : JsonSerializerContext;
 }

Original file line number	Diff line number	Diff line change
`@@ -71,6 +71,7 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(`
`71`	`71`	`Description = options?.Description,`
`72`	`72`	`MarshalResult = static (result, _, cancellationToken) => new ValueTask<object?>(result),`
`73`	`73`	`SerializerOptions = options?.SerializerOptions ?? McpJsonUtilities.DefaultOptions,`
	`74`	`+ JsonSchemaCreateOptions = options?.SchemaCreateOptions,`
`74`	`75`	`ConfigureParameterBinding = pi =>`
`75`	`76`	`{`
`76`	`77`	`if (pi.ParameterType == typeof(RequestContext<GetPromptRequestParams>))`
`@@ -151,7 +152,6 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(`
`151`	`152`	`return null;`
`152`	`153`	`}`
`153`	`154`	`},`
`154`		`- JsonSchemaCreateOptions = options?.SchemaCreateOptions,`
`155`	`155`	`};`
`156`	`156`
`157`	`157`	`/// <summary>Creates an <see cref="McpServerPrompt"/> that wraps the specified <see cref="AIFunction"/>.</summary>`
Original file line number	Diff line number	Diff line change
`@@ -86,6 +86,7 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(`
`86`	`86`	`Description = options?.Description,`
`87`	`87`	`MarshalResult = static (result, _, cancellationToken) => new ValueTask<object?>(result),`
`88`	`88`	`SerializerOptions = options?.SerializerOptions ?? McpJsonUtilities.DefaultOptions,`
	`89`	`+ JsonSchemaCreateOptions = options?.SchemaCreateOptions,`
`89`	`90`	`ConfigureParameterBinding = pi =>`
`90`	`91`	`{`
`91`	`92`	`if (pi.ParameterType == typeof(RequestContext<CallToolRequestParams>))`
`@@ -166,7 +167,6 @@ private static AIFunctionFactoryOptions CreateAIFunctionFactoryOptions(`
`166`	`167`	`return null;`
`167`	`168`	`}`
`168`	`169`	`},`
`169`		`- JsonSchemaCreateOptions = options?.SchemaCreateOptions,`
`170`	`170`	`};`
`171`	`171`
`172`	`172`	`/// <summary>Creates an <see cref="McpServerTool"/> that wraps the specified <see cref="AIFunction"/>.</summary>`
`@@ -366,7 +366,7 @@ public override async ValueTask<CallToolResponse> InvokeAsync(`
`366`	`366`	`return null;`
`367`	`367`	`}`
`368`	`368`
`369`		`- if (function.GetReturnSchema(toolCreateOptions?.SchemaCreateOptions) is not JsonElement outputSchema)`
	`369`	`+ if (function.ReturnJsonSchema is not JsonElement outputSchema)`
`370`	`370`	`{`
`371`	`371`	`return null;`
`372`	`372`	`}`
Original file line number	Diff line number	Diff line change
`@@ -5,6 +5,8 @@`
`5`	`5`	`using Moq;`
`6`	`6`	`using System.ComponentModel;`
`7`	`7`	`using System.Reflection;`
	`8`	`+using System.Text.Json;`
	`9`	`+using System.Text.Json.Nodes;`
`8`	`10`
`9`	`11`	`namespace ModelContextProtocol.Tests.Server;`
`10`	`12`
`@@ -324,6 +326,11 @@ public async Task SupportsSchemaCreateOptions()`
`324`	`326`	`{`
`325`	`327`	`TransformSchemaNode = (context, node) =>`
`326`	`328`	`{`
	`329`	`+ if (node.GetValueKind() is not JsonValueKind.Object)`
	`330`	`+ {`
	`331`	`+ node = new JsonObject();`
	`332`	`+ }`
	`333`	`+`
`327`	`334`	`node["description"] = "1234";`
`328`	`335`	`return node;`
`329`	`336`	`}`