Remove server back-references from protocol DTO types (#1345)

Copilot · stephentoub · web-flow · commit 74622d0c9c97 · 2026-02-23T14:17:54.000-05:00
Co-authored-by: copilot-swe-agent[bot] &lt;198982749+Copilot@users.noreply.github.com&gt;
Co-authored-by: stephentoub &lt;2642209+stephentoub@users.noreply.github.com&gt;
Co-authored-by: Stephen Toub &lt;stoub@microsoft.com&gt;
diff --git a/src/ModelContextProtocol.AspNetCore/AuthorizationFilterSetup.cs b/src/ModelContextProtocol.AspNetCore/AuthorizationFilterSetup.cs
@@ -43,31 +43,39 @@ public void PostConfigure(string? name, McpServerOptions options)
 
     private void ConfigureListToolsFilter(McpServerOptions options)
     {
-        options.Filters.Request.ListToolsFilters.Add(next => async (context, cancellationToken) =>
+        options.Filters.Request.ListToolsFilters.Add(next =>
         {
-            context.Items[AuthorizationFilterInvokedKey] = true;
-
-            var result = await next(context, cancellationToken);
-            await FilterAuthorizedItemsAsync(
-                result.Tools, static tool => tool.McpServerTool,
-                context.User, context.Services, context);
-            return result;
+            var toolCollection = options.ToolCollection;
+            return async (context, cancellationToken) =>
+            {
+                context.Items[AuthorizationFilterInvokedKey] = true;
+
+                var result = await next(context, cancellationToken);
+                await FilterAuthorizedItemsAsync(
+                    result.Tools, tool => toolCollection is not null && toolCollection.TryGetPrimitive(tool.Name, out var serverTool) ? serverTool : null,
+                    context.User, context.Services, context);
+                return result;
+            };
         });
     }
 
     private static void CheckListToolsFilter(McpServerOptions options)
     {
-        options.Filters.Request.ListToolsFilters.Add(next => async (context, cancellationToken) =>
+        options.Filters.Request.ListToolsFilters.Add(next =>
         {
-            var result = await next(context, cancellationToken);
-
-            if (HasAuthorizationMetadata(result.Tools.Select(static tool => tool.McpServerTool))
-                && !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
+            var toolCollection = options.ToolCollection;
+            return async (context, cancellationToken) =>
             {
-                throw new InvalidOperationException("Authorization filter was not invoked for tools/list operation, but authorization metadata was found on the tools. Ensure that AddAuthorizationFilters() is called on the IMcpServerBuilder to configure authorization filters.");
-            }
+                var result = await next(context, cancellationToken);
+
+                if (HasAuthorizationMetadata(result.Tools.Select(tool => toolCollection is not null && toolCollection.TryGetPrimitive(tool.Name, out var serverTool) ? serverTool : null))
+                    && !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
+                {
+                    throw new InvalidOperationException("Authorization filter was not invoked for tools/list operation, but authorization metadata was found on the tools. Ensure that AddAuthorizationFilters() is called on the IMcpServerBuilder to configure authorization filters.");
+                }
 
-            return result;
+                return result;
+            };
         });
     }
 
@@ -103,61 +111,77 @@ private static void CheckCallToolFilter(McpServerOptions options)
 
     private void ConfigureListResourcesFilter(McpServerOptions options)
     {
-        options.Filters.Request.ListResourcesFilters.Add(next => async (context, cancellationToken) =>
+        options.Filters.Request.ListResourcesFilters.Add(next =>
         {
-            context.Items[AuthorizationFilterInvokedKey] = true;
-
-            var result = await next(context, cancellationToken);
-            await FilterAuthorizedItemsAsync(
-                result.Resources, static resource => resource.McpServerResource,
-                context.User, context.Services, context);
-            return result;
+            var resourceCollection = options.ResourceCollection;
+            return async (context, cancellationToken) =>
+            {
+                context.Items[AuthorizationFilterInvokedKey] = true;
+
+                var result = await next(context, cancellationToken);
+                await FilterAuthorizedItemsAsync(
+                    result.Resources, resource => resourceCollection is not null && resourceCollection.TryGetPrimitive(resource.Uri, out var serverResource) ? serverResource : null,
+                    context.User, context.Services, context);
+                return result;
+            };
         });
     }
 
     private static void CheckListResourcesFilter(McpServerOptions options)
     {
-        options.Filters.Request.ListResourcesFilters.Add(next => async (context, cancellationToken) =>
+        options.Filters.Request.ListResourcesFilters.Add(next =>
         {
-            var result = await next(context, cancellationToken);
-
-            if (HasAuthorizationMetadata(result.Resources.Select(static resource => resource.McpServerResource))
-                && !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
+            var resourceCollection = options.ResourceCollection;
+            return async (context, cancellationToken) =>
             {
-                throw new InvalidOperationException("Authorization filter was not invoked for resources/list operation, but authorization metadata was found on the resources. Ensure that AddAuthorizationFilters() is called on the IMcpServerBuilder to configure authorization filters.");
-            }
+                var result = await next(context, cancellationToken);
+
+                if (HasAuthorizationMetadata(result.Resources.Select(resource => resourceCollection is not null && resourceCollection.TryGetPrimitive(resource.Uri, out var serverResource) ? serverResource : null))
+                    && !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
+                {
+                    throw new InvalidOperationException("Authorization filter was not invoked for resources/list operation, but authorization metadata was found on the resources. Ensure that AddAuthorizationFilters() is called on the IMcpServerBuilder to configure authorization filters.");
+                }
 
-            return result;
+                return result;
+            };
         });
     }
 
     private void ConfigureListResourceTemplatesFilter(McpServerOptions options)
     {
-        options.Filters.Request.ListResourceTemplatesFilters.Add(next => async (context, cancellationToken) =>
+        options.Filters.Request.ListResourceTemplatesFilters.Add(next =>
         {
-            context.Items[AuthorizationFilterInvokedKey] = true;
-
-            var result = await next(context, cancellationToken);
-            await FilterAuthorizedItemsAsync(
-                result.ResourceTemplates, static resourceTemplate => resourceTemplate.McpServerResource,
-                context.User, context.Services, context);
-            return result;
+            var resourceCollection = options.ResourceCollection;
+            return async (context, cancellationToken) =>
+            {
+                context.Items[AuthorizationFilterInvokedKey] = true;
+
+                var result = await next(context, cancellationToken);
+                await FilterAuthorizedItemsAsync(
+                    result.ResourceTemplates, resourceTemplate => resourceCollection is not null && resourceCollection.TryGetPrimitive(resourceTemplate.UriTemplate, out var serverResource) ? serverResource : null,
+                    context.User, context.Services, context);
+                return result;
+            };
         });
     }
 
     private static void CheckListResourceTemplatesFilter(McpServerOptions options)
     {
-        options.Filters.Request.ListResourceTemplatesFilters.Add(next => async (context, cancellationToken) =>
+        options.Filters.Request.ListResourceTemplatesFilters.Add(next =>
         {
-            var result = await next(context, cancellationToken);
-
-            if (HasAuthorizationMetadata(result.ResourceTemplates.Select(static resourceTemplate => resourceTemplate.McpServerResource))
-                && !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
+            var resourceCollection = options.ResourceCollection;
+            return async (context, cancellationToken) =>
             {
-                throw new InvalidOperationException("Authorization filter was not invoked for resources/templates/list operation, but authorization metadata was found on the resource templates. Ensure that AddAuthorizationFilters() is called on the IMcpServerBuilder to configure authorization filters.");
-            }
+                var result = await next(context, cancellationToken);
+
+                if (HasAuthorizationMetadata(result.ResourceTemplates.Select(resourceTemplate => resourceCollection is not null && resourceCollection.TryGetPrimitive(resourceTemplate.UriTemplate, out var serverResource) ? serverResource : null))
+                    && !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
+                {
+                    throw new InvalidOperationException("Authorization filter was not invoked for resources/templates/list operation, but authorization metadata was found on the resource templates. Ensure that AddAuthorizationFilters() is called on the IMcpServerBuilder to configure authorization filters.");
+                }
 
-            return result;
+                return result;
+            };
         });
     }
 
@@ -193,31 +217,39 @@ private static void CheckReadResourceFilter(McpServerOptions options)
 
     private void ConfigureListPromptsFilter(McpServerOptions options)
     {
-        options.Filters.Request.ListPromptsFilters.Add(next => async (context, cancellationToken) =>
+        options.Filters.Request.ListPromptsFilters.Add(next =>
         {
-            context.Items[AuthorizationFilterInvokedKey] = true;
-
-            var result = await next(context, cancellationToken);
-            await FilterAuthorizedItemsAsync(
-                result.Prompts, static prompt => prompt.McpServerPrompt,
-                context.User, context.Services, context);
-            return result;
+            var promptCollection = options.PromptCollection;
+            return async (context, cancellationToken) =>
+            {
+                context.Items[AuthorizationFilterInvokedKey] = true;
+
+                var result = await next(context, cancellationToken);
+                await FilterAuthorizedItemsAsync(
+                    result.Prompts, prompt => promptCollection is not null && promptCollection.TryGetPrimitive(prompt.Name, out var serverPrompt) ? serverPrompt : null,
+                    context.User, context.Services, context);
+                return result;
+            };
         });
     }
 
     private static void CheckListPromptsFilter(McpServerOptions options)
     {
-        options.Filters.Request.ListPromptsFilters.Add(next => async (context, cancellationToken) =>
+        options.Filters.Request.ListPromptsFilters.Add(next =>
         {
-            var result = await next(context, cancellationToken);
-
-            if (HasAuthorizationMetadata(result.Prompts.Select(static prompt => prompt.McpServerPrompt))
-                && !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
+            var promptCollection = options.PromptCollection;
+            return async (context, cancellationToken) =>
             {
-                throw new InvalidOperationException("Authorization filter was not invoked for prompts/list operation, but authorization metadata was found on the prompts. Ensure that AddAuthorizationFilters() is called on the IMcpServerBuilder to configure authorization filters.");
-            }
+                var result = await next(context, cancellationToken);
+
+                if (HasAuthorizationMetadata(result.Prompts.Select(prompt => promptCollection is not null && promptCollection.TryGetPrimitive(prompt.Name, out var serverPrompt) ? serverPrompt : null))
+                    && !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
+                {
+                    throw new InvalidOperationException("Authorization filter was not invoked for prompts/list operation, but authorization metadata was found on the prompts. Ensure that AddAuthorizationFilters() is called on the IMcpServerBuilder to configure authorization filters.");
+                }
 
-            return result;
+                return result;
+            };
         });
     }
 
diff --git a/src/ModelContextProtocol.Core/Protocol/Prompt.cs b/src/ModelContextProtocol.Core/Protocol/Prompt.cs
@@ -1,7 +1,6 @@
 using System.Diagnostics;
 using System.Text.Json.Nodes;
 using System.Text.Json.Serialization;
-using ModelContextProtocol.Server;
 
 namespace ModelContextProtocol.Protocol;
 
@@ -72,12 +71,6 @@ public sealed class Prompt : IBaseMetadata
     [JsonPropertyName("_meta")]
     public JsonObject? Meta { get; set; }
 
-    /// <summary>
-    /// Gets or sets the callable server prompt corresponding to this metadata if any.
-    /// </summary>
-    [JsonIgnore]
-    public McpServerPrompt? McpServerPrompt { get; set; }
-
     [DebuggerBrowsable(DebuggerBrowsableState.Never)]
     private string DebuggerDisplay
     {
diff --git a/src/ModelContextProtocol.Core/Protocol/Resource.cs b/src/ModelContextProtocol.Core/Protocol/Resource.cs
@@ -2,7 +2,6 @@
 using System.Diagnostics.CodeAnalysis;
 using System.Text.Json.Nodes;
 using System.Text.Json.Serialization;
-using ModelContextProtocol.Server;
 
 namespace ModelContextProtocol.Protocol;
 
@@ -101,10 +100,4 @@ public sealed class Resource : IBaseMetadata
     /// </remarks>
     [JsonPropertyName("_meta")]
     public JsonObject? Meta { get; set; }
-
-    /// <summary>
-    /// Gets or sets the callable server resource corresponding to this metadata if any.
-    /// </summary>
-    [JsonIgnore]
-    public McpServerResource? McpServerResource { get; set; }
 }
diff --git a/src/ModelContextProtocol.Core/Protocol/ResourceTemplate.cs b/src/ModelContextProtocol.Core/Protocol/ResourceTemplate.cs
@@ -1,6 +1,5 @@
 using System.Text.Json.Nodes;
 using System.Text.Json.Serialization;
-using ModelContextProtocol.Server;
 
 namespace ModelContextProtocol.Protocol;
 
@@ -94,12 +93,6 @@ public sealed class ResourceTemplate : IBaseMetadata
     [JsonIgnore]
     public bool IsTemplated => UriTemplate.Contains('{');
 
-    /// <summary>
-    /// Gets or sets the callable server resource corresponding to this metadata, if any.
-    /// </summary>
-    [JsonIgnore]
-    public McpServerResource? McpServerResource { get; set; }
-
     /// <summary>Converts the <see cref="ResourceTemplate"/> into a <see cref="Resource"/>.</summary>
     /// <returns>A <see cref="Resource"/> if <see cref="IsTemplated"/> is <see langword="false"/>; otherwise, <see langword="null"/>.</returns>
     public Resource? AsResource()
@@ -119,7 +112,6 @@ public sealed class ResourceTemplate : IBaseMetadata
             Annotations = Annotations,
             Icons = Icons,
             Meta = Meta,
-            McpServerResource = McpServerResource,
         };
     }
 }
diff --git a/src/ModelContextProtocol.Core/Protocol/Tool.cs b/src/ModelContextProtocol.Core/Protocol/Tool.cs
@@ -1,4 +1,3 @@
-using ModelContextProtocol.Server;
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.Text.Json;
@@ -158,12 +157,6 @@ public ToolExecution? Execution
     [JsonPropertyName("_meta")]
     public JsonObject? Meta { get; set; }
 
-    /// <summary>
-    /// Gets or sets the callable server tool corresponding to this metadata if any.
-    /// </summary>
-    [JsonIgnore]
-    public McpServerTool? McpServerTool { get; set; }
-
     [DebuggerBrowsable(DebuggerBrowsableState.Never)]
     private string DebuggerDisplay
     {
diff --git a/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerPrompt.cs b/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerPrompt.cs
@@ -182,7 +182,6 @@ private AIFunctionMcpServerPrompt(AIFunction function, Prompt prompt, IReadOnlyL
     {
         AIFunction = function;
         ProtocolPrompt = prompt;
-        ProtocolPrompt.McpServerPrompt = this;
         _metadata = metadata;
     }
 
diff --git a/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerResource.cs b/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerResource.cs
@@ -294,7 +294,6 @@ private AIFunctionMcpServerResource(AIFunction function, ResourceTemplate resour
     {
         AIFunction = function;
         ProtocolResourceTemplate = resourceTemplate;
-        ProtocolResourceTemplate.McpServerResource = this;
         ProtocolResource = resourceTemplate.AsResource();
         _metadata = metadata;
 
diff --git a/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerTool.cs b/src/ModelContextProtocol.Core/Server/AIFunctionMcpServerTool.cs
@@ -234,7 +234,6 @@ private AIFunctionMcpServerTool(AIFunction function, Tool tool, IServiceProvider
 
         AIFunction = function;
         ProtocolTool = tool;
-        ProtocolTool.McpServerTool = this;
 
         _structuredOutputRequiresWrapping = structuredOutputRequiresWrapping;
         _metadata = metadata;
diff --git a/tests/ModelContextProtocol.AspNetCore.Tests/AuthorizeAttributeTests.cs b/tests/ModelContextProtocol.AspNetCore.Tests/AuthorizeAttributeTests.cs

Original file line number	Diff line number	Diff line change
`@@ -182,7 +182,6 @@ private AIFunctionMcpServerPrompt(AIFunction function, Prompt prompt, IReadOnlyL`
`182`	`182`	`{`
`183`	`183`	`AIFunction = function;`
`184`	`184`	`ProtocolPrompt = prompt;`
`185`		`- ProtocolPrompt.McpServerPrompt = this;`
`186`	`185`	`_metadata = metadata;`
`187`	`186`	`}`
`188`	`187`
Original file line number	Diff line number	Diff line change
`@@ -294,7 +294,6 @@ private AIFunctionMcpServerResource(AIFunction function, ResourceTemplate resour`
`294`	`294`	`{`
`295`	`295`	`AIFunction = function;`
`296`	`296`	`ProtocolResourceTemplate = resourceTemplate;`
`297`		`- ProtocolResourceTemplate.McpServerResource = this;`
`298`	`297`	`ProtocolResource = resourceTemplate.AsResource();`
`299`	`298`	`_metadata = metadata;`
`300`	`299`