ChilliCream · glen-84 · Aug 25, 2025 · Aug 30, 2025 · Sep 2, 2025
diff --git a/src/All.slnx b/src/All.slnx
@@ -217,7 +217,9 @@
   </Folder>
   <Folder Name="/HotChocolate/ModelContextProtocol/" />
   <Folder Name="/HotChocolate/ModelContextProtocol/src/">
+    <Project Path="HotChocolate/ModelContextProtocol/src/HotChocolate.Fusion.ModelContextProtocol/HotChocolate.Fusion.ModelContextProtocol.csproj" />
     <Project Path="HotChocolate/ModelContextProtocol/src/HotChocolate.ModelContextProtocol/HotChocolate.ModelContextProtocol.csproj" />
+    <Project Path="HotChocolate/ModelContextProtocol/src/HotChocolate.ModelContextProtocol.Core/HotChocolate.ModelContextProtocol.Core.csproj" />
   </Folder>
   <Folder Name="/HotChocolate/ModelContextProtocol/test/">
     <Project Path="HotChocolate/ModelContextProtocol/test/HotChocolate.ModelContextProtocol.Tests/HotChocolate.ModelContextProtocol.Tests.csproj" />
@@ -349,4 +351,4 @@
   <Folder Name="/StrawberryShake/Tooling/test/">
     <Project Path="StrawberryShake/Tooling/test/Configuration.Tests/StrawberryShake.Tools.Configuration.Tests.csproj" />
   </Folder>
-</Solution>
+</Solution>
diff --git a/.../HotChocolate.Fusion.ModelContextProtocol/HotChocolate.Fusion.ModelContextProtocol.csproj b/.../HotChocolate.Fusion.ModelContextProtocol/HotChocolate.Fusion.ModelContextProtocol.csproj
@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <AssemblyName>HotChocolate.ModelContextProtocol.Fusion</AssemblyName>
+    <RootNamespace>HotChocolate.ModelContextProtocol</RootNamespace>
+  </PropertyGroup>
+
+</Project>
diff --git a/...Directives/McpToolAnnotationsDirective.cs → ...Directives/McpToolAnnotationsDirective.cs b/...Directives/McpToolAnnotationsDirective.cs → ...Directives/McpToolAnnotationsDirective.cs
diff --git a/...xtProtocol/Directives/McpToolDirective.cs → ...tocol.Core/Directives/McpToolDirective.cs b/...xtProtocol/Directives/McpToolDirective.cs → ...tocol.Core/Directives/McpToolDirective.cs
diff --git a/...ocol/Directives/McpToolDirectiveParser.cs → ...Core/Directives/McpToolDirectiveParser.cs b/...ocol/Directives/McpToolDirectiveParser.cs → ...Core/Directives/McpToolDirectiveParser.cs
diff --git a/...ensions/EndpointRouteBuilderExtensions.cs → ...ensions/EndpointRouteBuilderExtensions.cs b/...ensions/EndpointRouteBuilderExtensions.cs → ...ensions/EndpointRouteBuilderExtensions.cs
diff --git a/...rotocol/Extensions/FieldNodeExtensions.cs → ...ol.Core/Extensions/FieldNodeExtensions.cs b/...rotocol/Extensions/FieldNodeExtensions.cs → ...ol.Core/Extensions/FieldNodeExtensions.cs
diff --git a/...col/Extensions/HasDirectivesExtensions.cs → ...ore/Extensions/HasDirectivesExtensions.cs b/...col/Extensions/HasDirectivesExtensions.cs → ...ore/Extensions/HasDirectivesExtensions.cs
diff --git a/...otocol/Extensions/InputFieldExtensions.cs → ...ensions/InputValueDefinitionExtensions.cs b/...otocol/Extensions/InputFieldExtensions.cs → ...ensions/InputValueDefinitionExtensions.cs
@@ -3,12 +3,12 @@
 
 namespace HotChocolate.ModelContextProtocol.Extensions;
 
-internal static class InputFieldExtensions
+internal static class InputValueDefinitionExtensions
 {
-    public static JsonSchema ToJsonSchema(this InputField inputField)
+    public static JsonSchema ToJsonSchema(this IInputValueDefinition inputField)
     {
         var type = inputField.Type;
         var schemaBuilder = type.ToJsonSchemaBuilder(isOneOf: inputField.DeclaringType.IsOneOf);

        // Description.
        if (inputField.Description is not null)

diff --git a/...otocol/Extensions/JsonSchemaExtensions.cs → ...l.Core/Extensions/JsonSchemaExtensions.cs b/...otocol/Extensions/JsonSchemaExtensions.cs → ...l.Core/Extensions/JsonSchemaExtensions.cs
diff --git a/...ions/OperationDefinitionNodeExtensions.cs → ...ions/OperationDefinitionNodeExtensions.cs b/...ions/OperationDefinitionNodeExtensions.cs → ...ions/OperationDefinitionNodeExtensions.cs
diff --git a/...nsions/OutputFieldDefinitionExtensions.cs → ...nsions/OutputFieldDefinitionExtensions.cs b/...nsions/OutputFieldDefinitionExtensions.cs → ...nsions/OutputFieldDefinitionExtensions.cs
diff --git a/...textProtocol/Extensions/TypeExtensions.cs → ...rotocol.Core/Extensions/TypeExtensions.cs b/...textProtocol/Extensions/TypeExtensions.cs → ...rotocol.Core/Extensions/TypeExtensions.cs
@@ -49,7 +49,7 @@
 
         switch (type.NullableType())
         {
-            case EnumType enumType:
+            case IEnumTypeDefinition enumType:
                 // Enum values.
                 List<JsonValue?> enumValues = [];
 
@@ -66,7 +66,7 @@
                 schemaBuilder.Enum(enumValues);
                 break;
 
-            case InputObjectType inputObjectType:
+            case IInputObjectTypeDefinition inputObjectType:
                 // Object properties.
                 var objectProperties = new Dictionary<string, JsonSchema>();
                 var requiredObjectProperties = new List<string>();
@@ -84,7 +84,7 @@
                }

                // OneOf.
                if (inputObjectType.IsOneOf)
                {
                    List<JsonSchema> oneOfSchemas = [];

@@ -123,21 +123,22 @@
     {
         return type switch
         {
-            EnumType => SchemaValueType.String,
-            InputObjectType or InterfaceType or ObjectType or UnionType => SchemaValueType.Object,
+            IEnumTypeDefinition => SchemaValueType.String,
+            IInputObjectTypeDefinition or IInterfaceTypeDefinition or IObjectTypeDefinition or IUnionTypeDefinition
+                => SchemaValueType.Object,
             ListType => SchemaValueType.Array,
             NonNullType => GetJsonSchemaValueType(type.NullableType()),
-            ScalarType => type switch
+            IScalarTypeDefinition => type switch
             {
                 AnyType or JsonType =>
                     SchemaValueType.Object
                    | SchemaValueType.Array
                    | SchemaValueType.Boolean
                    | SchemaValueType.String
                    | SchemaValueType.Number
                    | SchemaValueType.Integer,
                BooleanType => SchemaValueType.Boolean,
                ByteType or IntType or LongType or ShortType => SchemaValueType.Integer,
                DecimalType or FloatType => SchemaValueType.Number,
                IdType or StringType => SchemaValueType.String,
                // The following types are serialized as strings:

diff --git a/...Protocol/Extensions/TypeNodeExtensions.cs → ...col.Core/Extensions/TypeNodeExtensions.cs b/...Protocol/Extensions/TypeNodeExtensions.cs → ...col.Core/Extensions/TypeNodeExtensions.cs
diff --git a/...rotocol/Extensions/ValueNodeExtensions.cs → ...ol.Core/Extensions/ValueNodeExtensions.cs b/...rotocol/Extensions/ValueNodeExtensions.cs → ...ol.Core/Extensions/ValueNodeExtensions.cs
@@ -63,7 +63,7 @@ private static JsonObject ToJsonNode(this ObjectValueNode valueNode, IType objec
 
         foreach (var field in valueNode.Fields)
         {
-            var graphQLFieldType = objectType is InputObjectType inputObjectType
+            var graphQLFieldType = objectType is IInputObjectTypeDefinition inputObjectType
                 ? inputObjectType.Fields[field.Name.Value].Type
                 : new AnyType(); // Types like JsonType or AnyType have no schema.
 

diff --git a/...ntextProtocol/Handlers/CallToolHandler.cs → ...Protocol.Core/Handlers/CallToolHandler.cs b/...ntextProtocol/Handlers/CallToolHandler.cs → ...Protocol.Core/Handlers/CallToolHandler.cs
diff --git a/...textProtocol/Handlers/ListToolsHandler.cs → ...rotocol.Core/Handlers/ListToolsHandler.cs b/...textProtocol/Handlers/ListToolsHandler.cs → ...rotocol.Core/Handlers/ListToolsHandler.cs
diff --git a/.../src/HotChocolate.ModelContextProtocol.Core/HotChocolate.ModelContextProtocol.Core.csproj b/.../src/HotChocolate.ModelContextProtocol.Core/HotChocolate.ModelContextProtocol.Core.csproj
@@ -0,0 +1,41 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <AssemblyName>HotChocolate.ModelContextProtocol.Core</AssemblyName>
+    <RootNamespace>HotChocolate.ModelContextProtocol</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <InternalsVisibleTo Include="HotChocolate.ModelContextProtocol" />
+    <InternalsVisibleTo Include="HotChocolate.ModelContextProtocol.Tests" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="CaseConverter" />
+    <PackageReference Include="ChilliCream.ModelContextProtocol.AspNetCore" />
+    <PackageReference Include="JsonSchema.Net" />
+    <PackageReference Include="System.Reactive" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\..\Core\src\Execution.Abstractions\HotChocolate.Execution.Abstractions.csproj" />
+    <ProjectReference Include="..\..\..\Core\src\Types.Abstractions\HotChocolate.Types.Abstractions.csproj" />
+    <ProjectReference Include="..\..\..\Language\src\Language\HotChocolate.Language.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <EmbeddedResource Update="Properties\ModelContextProtocolResources.resx">
+      <Generator>ResXFileCodeGenerator</Generator>
+      <LastGenOutput>ModelContextProtocolResources.Designer.cs</LastGenOutput>
+    </EmbeddedResource>
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Update="Properties\ModelContextProtocolResources.Designer.cs">
+      <DesignTime>True</DesignTime>
+      <AutoGen>True</AutoGen>
+      <DependentUpon>ModelContextProtocolResources.resx</DependentUpon>
+    </Compile>
+  </ItemGroup>
+
+</Project>
diff --git a/...otocol/JsonSchemaJsonSerializerContext.cs → ...l.Core/JsonSchemaJsonSerializerContext.cs b/...otocol/JsonSchemaJsonSerializerContext.cs → ...l.Core/JsonSchemaJsonSerializerContext.cs
diff --git a/...ate.ModelContextProtocol/OperationTool.cs → ...odelContextProtocol.Core/OperationTool.cs b/...ate.ModelContextProtocol/OperationTool.cs → ...odelContextProtocol.Core/OperationTool.cs
diff --git a/...elContextProtocol/OperationToolFactory.cs → ...textProtocol.Core/OperationToolFactory.cs b/...elContextProtocol/OperationToolFactory.cs → ...textProtocol.Core/OperationToolFactory.cs
diff --git a/...ModelContextProtocolResources.Designer.cs → ...ModelContextProtocolResources.Designer.cs b/...ModelContextProtocolResources.Designer.cs → ...ModelContextProtocolResources.Designer.cs
diff --git a/...erties/ModelContextProtocolResources.resx → ...erties/ModelContextProtocolResources.resx b/...erties/ModelContextProtocolResources.resx → ...erties/ModelContextProtocolResources.resx
diff --git a/...extProtocol/Proxies/McpExecutorSession.cs → ...otocol.Core/Proxies/McpExecutorSession.cs b/...extProtocol/Proxies/McpExecutorSession.cs → ...otocol.Core/Proxies/McpExecutorSession.cs
diff --git a/...otocol/Proxies/McpRequestExecutorProxy.cs → ...l.Core/Proxies/McpRequestExecutorProxy.cs b/...otocol/Proxies/McpRequestExecutorProxy.cs → ...l.Core/Proxies/McpRequestExecutorProxy.cs
diff --git a/...ontextProtocol/Proxies/SseHandlerProxy.cs → ...tProtocol.Core/Proxies/SseHandlerProxy.cs b/...ontextProtocol/Proxies/SseHandlerProxy.cs → ...tProtocol.Core/Proxies/SseHandlerProxy.cs
diff --git a/...col/Proxies/StreamableHttpHandlerProxy.cs → ...ore/Proxies/StreamableHttpHandlerProxy.cs b/...col/Proxies/StreamableHttpHandlerProxy.cs → ...ore/Proxies/StreamableHttpHandlerProxy.cs
diff --git a/...Protocol/Storage/IOperationToolStorage.cs → ...col.Core/Storage/IOperationToolStorage.cs b/...Protocol/Storage/IOperationToolStorage.cs → ...col.Core/Storage/IOperationToolStorage.cs
diff --git a/...otocol/Storage/OperationToolDefinition.cs → ...l.Core/Storage/OperationToolDefinition.cs b/...otocol/Storage/OperationToolDefinition.cs → ...l.Core/Storage/OperationToolDefinition.cs
diff --git a/.../Storage/OperationToolStorageEventArgs.cs → .../Storage/OperationToolStorageEventArgs.cs b/.../Storage/OperationToolStorageEventArgs.cs → .../Storage/OperationToolStorageEventArgs.cs
diff --git a/.../Storage/OperationToolStorageEventType.cs → .../Storage/OperationToolStorageEventType.cs b/.../Storage/OperationToolStorageEventType.cs → .../Storage/OperationToolStorageEventType.cs
diff --git a/...late.ModelContextProtocol/ToolRegistry.cs → ...ModelContextProtocol.Core/ToolRegistry.cs b/...late.ModelContextProtocol/ToolRegistry.cs → ...ModelContextProtocol.Core/ToolRegistry.cs
diff --git a/...delContextProtocol/ToolStorageObserver.cs → ...ntextProtocol.Core/ToolStorageObserver.cs b/...delContextProtocol/ToolStorageObserver.cs → ...ntextProtocol.Core/ToolStorageObserver.cs
diff --git a/...ContextProtocol/WellKnownArgumentNames.cs → ...xtProtocol.Core/WellKnownArgumentNames.cs b/...ContextProtocol/WellKnownArgumentNames.cs → ...xtProtocol.Core/WellKnownArgumentNames.cs
diff --git a/...ontextProtocol/WellKnownDirectiveNames.cs → ...tProtocol.Core/WellKnownDirectiveNames.cs b/...ontextProtocol/WellKnownDirectiveNames.cs → ...tProtocol.Core/WellKnownDirectiveNames.cs
diff --git a/...delContextProtocol/WellKnownFieldNames.cs → ...ntextProtocol.Core/WellKnownFieldNames.cs b/...delContextProtocol/WellKnownFieldNames.cs → ...ntextProtocol.Core/WellKnownFieldNames.cs
diff --git a/...tProtocol/src/HotChocolate.ModelContextProtocol/Directives/McpToolAnnotationsAttribute.cs b/...tProtocol/src/HotChocolate.ModelContextProtocol/Directives/McpToolAnnotationsAttribute.cs
@@ -1,9 +1,8 @@
 using System.Reflection;
-using HotChocolate.ModelContextProtocol.Directives;
 using HotChocolate.Types;
 using HotChocolate.Types.Descriptors;
 
-namespace HotChocolate.ModelContextProtocol.Attributes;
+namespace HotChocolate.ModelContextProtocol.Directives;
 
 /// <summary>
 /// Additional properties describing a Tool to clients.

diff --git a/...tocol/src/HotChocolate.ModelContextProtocol/Directives/McpToolAnnotationsDirectiveType.cs b/...tocol/src/HotChocolate.ModelContextProtocol/Directives/McpToolAnnotationsDirectiveType.cs
@@ -1,7 +1,6 @@
-using HotChocolate.ModelContextProtocol.Directives;
 using HotChocolate.Types;
 
-namespace HotChocolate.ModelContextProtocol.Types;
+namespace HotChocolate.ModelContextProtocol.Directives;
 
 /// <summary>
 /// Additional properties describing a Tool to clients.

diff --git a/...ocol/src/HotChocolate.ModelContextProtocol/Extensions/RequestExecutorBuilderExtensions.cs b/...ocol/src/HotChocolate.ModelContextProtocol/Extensions/RequestExecutorBuilderExtensions.cs
@@ -1,9 +1,9 @@
 using HotChocolate.Execution;
 using HotChocolate.Execution.Configuration;
+using HotChocolate.ModelContextProtocol.Directives;
 using HotChocolate.ModelContextProtocol.Handlers;
 using HotChocolate.ModelContextProtocol.Proxies;
 using HotChocolate.ModelContextProtocol.Storage;
-using HotChocolate.ModelContextProtocol.Types;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
 using Microsoft.Extensions.Hosting;

diff --git a/...ntextProtocol/src/HotChocolate.ModelContextProtocol/Extensions/SchemaBuilderExtensions.cs b/...ntextProtocol/src/HotChocolate.ModelContextProtocol/Extensions/SchemaBuilderExtensions.cs
@@ -1,13 +1,13 @@
-using HotChocolate.ModelContextProtocol.Types;
-
-namespace HotChocolate.ModelContextProtocol.Extensions;
-
-public static class SchemaBuilderExtensions
-{
-    public static ISchemaBuilder AddMcp(this ISchemaBuilder builder)
-    {
-        builder.AddDirectiveType<McpToolAnnotationsDirectiveType>();
-
-        return builder;
-    }
-}
+using HotChocolate.ModelContextProtocol.Directives;
+
+namespace HotChocolate.ModelContextProtocol.Extensions;
+
+public static class SchemaBuilderExtensions
+{
+    public static ISchemaBuilder AddMcp(this ISchemaBuilder builder)
+    {
+        builder.AddDirectiveType<McpToolAnnotationsDirectiveType>();
+
+        return builder;
+    }
+}
diff --git a/...xtProtocol/src/HotChocolate.ModelContextProtocol/HotChocolate.ModelContextProtocol.csproj b/...xtProtocol/src/HotChocolate.ModelContextProtocol/HotChocolate.ModelContextProtocol.csproj
@@ -5,35 +5,10 @@
     <RootNamespace>HotChocolate.ModelContextProtocol</RootNamespace>
   </PropertyGroup>
 
-  <ItemGroup>
-    <InternalsVisibleTo Include="HotChocolate.ModelContextProtocol.Tests" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <PackageReference Include="CaseConverter" />
-    <PackageReference Include="ChilliCream.ModelContextProtocol.AspNetCore" />
-    <PackageReference Include="JsonSchema.Net" />
-    <PackageReference Include="System.Reactive" />
-  </ItemGroup>
-
   <ItemGroup>
     <ProjectReference Include="..\..\..\Core\src\Execution\HotChocolate.Execution.csproj" />
-    <ProjectReference Include="..\..\..\Language\src\Language\HotChocolate.Language.csproj" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <EmbeddedResource Update="Properties\ModelContextProtocolResources.resx">
-      <Generator>ResXFileCodeGenerator</Generator>
-      <LastGenOutput>ModelContextProtocolResources.Designer.cs</LastGenOutput>
-    </EmbeddedResource>
-  </ItemGroup>
-
-  <ItemGroup>
-    <Compile Update="Properties\ModelContextProtocolResources.Designer.cs">
-      <DesignTime>True</DesignTime>
-      <AutoGen>True</AutoGen>
-      <DependentUpon>ModelContextProtocolResources.resx</DependentUpon>
-    </Compile>
+    <ProjectReference Include="..\..\..\Core\src\Types\HotChocolate.Types.csproj" />
+    <ProjectReference Include="..\HotChocolate.ModelContextProtocol.Core\HotChocolate.ModelContextProtocol.Core.csproj" />
   </ItemGroup>
 
 </Project>
diff --git a/...Chocolate/ModelContextProtocol/test/HotChocolate.ModelContextProtocol.Tests/TestSchema.cs b/...Chocolate/ModelContextProtocol/test/HotChocolate.ModelContextProtocol.Tests/TestSchema.cs
@@ -4,7 +4,7 @@
 using System.Text.Json;
 using HotChocolate.Authorization;
 using HotChocolate.Language;
-using HotChocolate.ModelContextProtocol.Attributes;
+using HotChocolate.ModelContextProtocol.Directives;
 using HotChocolate.Types;
 
 namespace HotChocolate.ModelContextProtocol;