Add reflection-based tests validating delegating types override all base class members

Co-authored-by: stephentoub <2642209+stephentoub@users.noreply.github.com>

Author: Copilot

tests/ModelContextProtocol.Tests/Server/DelegatingMcpServerPrimitiveTests.cs

@@ -0,0 +1,36 @@
+using ModelContextProtocol.Server;
+using System.Reflection;
+
+namespace ModelContextProtocol.Tests.Server;
+
+public class DelegatingMcpServerPrimitiveTests
+{
+    [Theory]
+    [InlineData(typeof(DelegatingMcpServerTool), typeof(McpServerTool))]
+    [InlineData(typeof(DelegatingMcpServerPrompt), typeof(McpServerPrompt))]
+    [InlineData(typeof(DelegatingMcpServerResource), typeof(McpServerResource))]
+    public void DelegatingType_OverridesAllVirtualAndAbstractMembers(Type delegatingType, Type baseType)
+    {
+        // Get all public instance methods on the base type that are virtual/abstract
+        // (this includes property getters/setters) and declared on the base type itself,
+        // excluding those inherited from System.Object.
+        MethodInfo[] baseMethods = baseType.GetMethods(BindingFlags.Public | BindingFlags.Instance)
+            .Where(m => (m.IsVirtual || m.IsAbstract) && m.DeclaringType == baseType)
+            .ToArray();
+
+        Assert.NotEmpty(baseMethods);
+
+        foreach (MethodInfo baseMethod in baseMethods)
+        {
+            // Find the corresponding method on the delegating type
+            MethodInfo? overriddenMethod = delegatingType.GetMethod(
+                baseMethod.Name,
+                BindingFlags.Public | BindingFlags.Instance,
+                baseMethod.GetParameters().Select(p => p.ParameterType).ToArray());
+
+            Assert.True(
+                overriddenMethod is not null && overriddenMethod.DeclaringType == delegatingType,
+                $"{delegatingType.Name} does not override {baseMethod.Name} from {baseType.Name}.");
+        }
+    }
+}