Address code review: rename cryptic variables and add missing no-meta tests

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

Author: Copilot

src/ModelContextProtocol.Core/Server/AIFunctionMcpServerPrompt.cs

@@ -214,7 +214,7 @@ public override async ValueTask<GetPromptResult> GetAsync(
 
         GetPromptResult getPromptResult = result switch
         {
-            GetPromptResult gpr => gpr,
+            GetPromptResult existingResult => existingResult,
 
             string text => new()
             {

src/ModelContextProtocol.Core/Server/AIFunctionMcpServerResource.cs

@@ -377,7 +377,7 @@ public override async ValueTask<ReadResourceResult> ReadAsync(
         // And process the result.
         ReadResourceResult readResourceResult = result switch
         {
-            ReadResourceResult rrr => rrr,
+            ReadResourceResult existingResult => existingResult,
 
             ResourceContents content => new()
             {

src/ModelContextProtocol.Core/Server/AIFunctionMcpServerTool.cs

@@ -303,7 +303,7 @@ public override async ValueTask<CallToolResult> InvokeAsync(
                 StructuredContent = structuredContent,
             },
 
-            CallToolResult ctr => ctr,
+            CallToolResult existingResult => existingResult,
 
             _ => new()
             {

tests/ModelContextProtocol.Tests/Server/McpMetaAttributeTests.cs

@@ -1386,6 +1386,40 @@ public async Task McpServerTool_InvokeAsync_WithNoMeta_ResultHasNoMeta()
         Assert.Null(result.Meta);
     }
 
+    [Fact]
+    public async Task McpServerPrompt_GetAsync_WithNoMeta_ResultHasNoMeta()
+    {
+        var method = typeof(TestPromptMetaPropagationClass).GetMethod(nameof(TestPromptMetaPropagationClass.PromptWithoutMeta))!;
+        var prompt = McpServerPrompt.Create(method, target: null);
+
+        // Verify prompt has no meta defined
+        Assert.Null(prompt.ProtocolPrompt.Meta);
+
+        var result = await prompt.GetAsync(
+            new RequestContext<GetPromptRequestParams>(new Moq.Mock<McpServer>().Object, CreateTestJsonRpcRequest()) { Params = new() { Name = "prompt_without_meta" } },
+            TestContext.Current.CancellationToken);
+
+        // Verify result has no meta
+        Assert.Null(result.Meta);
+    }
+
+    [Fact]
+    public async Task McpServerResource_ReadAsync_WithNoMeta_ResultHasNoMeta()
+    {
+        var method = typeof(TestResourceMetaPropagationClass).GetMethod(nameof(TestResourceMetaPropagationClass.ResourceWithoutMeta))!;
+        var resource = McpServerResource.Create(method, target: null);
+
+        // Verify resource has no meta defined
+        Assert.Null(resource.ProtocolResourceTemplate?.Meta);
+
+        var result = await resource.ReadAsync(
+            new RequestContext<ReadResourceRequestParams>(new Moq.Mock<McpServer>().Object, CreateTestJsonRpcRequest()) { Params = new() { Uri = "resource://no-meta/123" } },
+            TestContext.Current.CancellationToken);
+
+        // Verify result has no meta
+        Assert.Null(result.Meta);
+    }
+
     private static JsonRpcRequest CreateTestJsonRpcRequest()
     {
         return new JsonRpcRequest
@@ -1414,6 +1448,15 @@ private class TestPromptMetaPropagationClass
         [McpMeta("type", "reasoning")]
         [McpMeta("model", "claude-3")]
         public static string PromptWithMeta() => "result";
+
+        [McpServerPrompt]
+        public static string PromptWithoutMeta() => "result";
+    }
+
+    private class TestResourceMetaPropagationClass
+    {
+        [McpServerResource(UriTemplate = "resource://no-meta/{id}")]
+        public static string ResourceWithoutMeta(string id) => id;
     }
 
     #endregion