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Split configuration of request and message filters (#1308)

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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
This commit is contained in:
Stephen Halter 2026-02-19 17:42:35 -08:00 • committed by GitHub
commit d21aa9e5a2
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16 changed files with 1288 additions and 1078 deletions
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5
src/Common/Obsoletions.cs
View file

@ -22,4 +22,9 @@ internal static class Obsoletions
public const string LegacyTitledEnumSchema_DiagnosticId = "MCP9001";
public const string LegacyTitledEnumSchema_Message = "The EnumSchema and LegacyTitledEnumSchema APIs are deprecated as of specification version 2025-11-25 and will be removed in a future major version. See SEP-1330 for more information.";
public const string LegacyTitledEnumSchema_Url = "https://github.com/modelcontextprotocol/modelcontextprotocol/issues/1330";
public const string MessageAndRequestFilter_DiagnosticId = "MCP9002";
public const string MessageAndRequestFilter_Url = "https://github.com/modelcontextprotocol/csharp-sdk/pull/1308";
public const string MessageFilter_Message = "Use WithMessageFilters() instead.";
public const string RequestFilter_Message = "Use WithRequestFilters() instead.";
}

28
src/ModelContextProtocol.AspNetCore/AuthorizationFilterSetup.cs
View file

@ -43,7 +43,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private void ConfigureListToolsFilter(McpServerOptions options)
{
options.Filters.ListToolsFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ListToolsFilters.Add(next => async (context, cancellationToken) =>
{
context.Items[AuthorizationFilterInvokedKey] = true;
@ -57,7 +57,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private static void CheckListToolsFilter(McpServerOptions options)
{
options.Filters.ListToolsFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ListToolsFilters.Add(next => async (context, cancellationToken) =>
{
var result = await next(context, cancellationToken);
@ -73,7 +73,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private void ConfigureCallToolFilter(McpServerOptions options)
{
options.Filters.CallToolFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.CallToolFilters.Add(next => async (context, cancellationToken) =>
{
var authResult = await GetAuthorizationResultAsync(context.User, context.MatchedPrimitive, context.Services, context);
if (!authResult.Succeeded)
@ -89,7 +89,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private static void CheckCallToolFilter(McpServerOptions options)
{
options.Filters.CallToolFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.CallToolFilters.Add(next => async (context, cancellationToken) =>
{
if (HasAuthorizationMetadata(context.MatchedPrimitive)
&& !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
@ -103,7 +103,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private void ConfigureListResourcesFilter(McpServerOptions options)
{
options.Filters.ListResourcesFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ListResourcesFilters.Add(next => async (context, cancellationToken) =>
{
context.Items[AuthorizationFilterInvokedKey] = true;
@ -117,7 +117,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private static void CheckListResourcesFilter(McpServerOptions options)
{
options.Filters.ListResourcesFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ListResourcesFilters.Add(next => async (context, cancellationToken) =>
{
var result = await next(context, cancellationToken);
@ -133,7 +133,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private void ConfigureListResourceTemplatesFilter(McpServerOptions options)
{
options.Filters.ListResourceTemplatesFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ListResourceTemplatesFilters.Add(next => async (context, cancellationToken) =>
{
context.Items[AuthorizationFilterInvokedKey] = true;
@ -147,7 +147,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private static void CheckListResourceTemplatesFilter(McpServerOptions options)
{
options.Filters.ListResourceTemplatesFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ListResourceTemplatesFilters.Add(next => async (context, cancellationToken) =>
{
var result = await next(context, cancellationToken);
@ -163,7 +163,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private void ConfigureReadResourceFilter(McpServerOptions options)
{
options.Filters.ReadResourceFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ReadResourceFilters.Add(next => async (context, cancellationToken) =>
{
context.Items[AuthorizationFilterInvokedKey] = true;
@ -179,7 +179,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private static void CheckReadResourceFilter(McpServerOptions options)
{
options.Filters.ReadResourceFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ReadResourceFilters.Add(next => async (context, cancellationToken) =>
{
if (HasAuthorizationMetadata(context.MatchedPrimitive)
&& !context.Items.ContainsKey(AuthorizationFilterInvokedKey))
@ -193,7 +193,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private void ConfigureListPromptsFilter(McpServerOptions options)
{
options.Filters.ListPromptsFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ListPromptsFilters.Add(next => async (context, cancellationToken) =>
{
context.Items[AuthorizationFilterInvokedKey] = true;
@ -207,7 +207,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private static void CheckListPromptsFilter(McpServerOptions options)
{
options.Filters.ListPromptsFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.ListPromptsFilters.Add(next => async (context, cancellationToken) =>
{
var result = await next(context, cancellationToken);
@ -223,7 +223,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private void ConfigureGetPromptFilter(McpServerOptions options)
{
options.Filters.GetPromptFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.GetPromptFilters.Add(next => async (context, cancellationToken) =>
{
context.Items[AuthorizationFilterInvokedKey] = true;
@ -239,7 +239,7 @@ internal sealed class AuthorizationFilterSetup(IAuthorizationPolicyProvider? pol
private static void CheckGetPromptFilter(McpServerOptions options)
{
options.Filters.GetPromptFilters.Add(next => async (context, cancellationToken) =>
options.Filters.Request.GetPromptFilters.Add(next => async (context, cancellationToken) =>
{
if (HasAuthorizationMetadata(context.MatchedPrimitive)
&& !context.Items.ContainsKey(AuthorizationFilterInvokedKey))

42
src/ModelContextProtocol.Core/Server/McpMessageFilters.cs Normal file
View file

@ -0,0 +1,42 @@
using ModelContextProtocol.Protocol;
namespace ModelContextProtocol.Server;
/// <summary>
/// Provides grouped message filter collections.
/// </summary>
public sealed class McpMessageFilters
{
/// <summary>
/// Gets the filters for all incoming JSON-RPC messages.
/// </summary>
/// <remarks>
/// <para>
/// These filters intercept all incoming JSON-RPC messages before they are processed by the server,
/// including requests, notifications, responses, and errors. The filters can perform logging,
/// authentication, rate limiting, or other cross-cutting concerns that apply to all message types.
/// </para>
/// <para>
/// Message filters are applied before request-specific filters. If a message filter does not call
/// the next handler in the pipeline, the default handlers will not be executed.
/// </para>
/// </remarks>
public IList<McpMessageFilter> IncomingFilters { get; } = [];
/// <summary>
/// Gets the filters for all outgoing JSON-RPC messages.
/// </summary>
/// <remarks>
/// <para>
/// These filters intercept all outgoing JSON-RPC messages before they are sent to the client,
/// including responses, notifications, and errors. The filters can perform logging,
/// redaction, auditing, or other cross-cutting concerns that apply to all message types.
/// </para>
/// <para>
/// If a message filter does not call the next handler in the pipeline, the message will not be sent.
/// Filters may also call the next handler multiple times with different messages to emit additional
/// server-to-client messages.
/// </para>
/// </remarks>
public IList<McpMessageFilter> OutgoingFilters { get; } = [];
}

157
src/ModelContextProtocol.Core/Server/McpRequestFilters.cs Normal file
View file

@ -0,0 +1,157 @@
using ModelContextProtocol.Protocol;
namespace ModelContextProtocol.Server;
/// <summary>
/// Provides grouped request-specific filter collections.
/// </summary>
public sealed class McpRequestFilters
{
/// <summary>
/// Gets the filters for the list-tools handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that return a list of available tools when requested by a client.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ToolsList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more tools.
/// </para>
/// <para>
/// These filters work alongside any tools defined in the <see cref="McpServerTool"/> collection.
/// Tools from both sources will be combined when returning results to clients.
/// </para>
/// </remarks>
public IList<McpRequestFilter<ListToolsRequestParams, ListToolsResult>> ListToolsFilters { get; } = [];
/// <summary>
/// Gets the filters for the call-tool handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that are invoked when a client makes a call to a tool that isn't found in the <see cref="McpServerTool"/> collection.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ToolsCall"/> requests. The handler should implement logic to execute the requested tool and return appropriate results.
/// </remarks>
public IList<McpRequestFilter<CallToolRequestParams, CallToolResult>> CallToolFilters { get; } = [];
/// <summary>
/// Gets the filters for the list-prompts handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that return a list of available prompts when requested by a client.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.PromptsList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more prompts.
/// </para>
/// <para>
/// These filters work alongside any prompts defined in the <see cref="McpServerPrompt"/> collection.
/// Prompts from both sources will be combined when returning results to clients.
/// </para>
/// </remarks>
public IList<McpRequestFilter<ListPromptsRequestParams, ListPromptsResult>> ListPromptsFilters { get; } = [];
/// <summary>
/// Gets the filters for the get-prompt handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that are invoked when a client requests details for a specific prompt that isn't found in the <see cref="McpServerPrompt"/> collection.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.PromptsGet"/> requests. The handler should implement logic to fetch or generate the requested prompt and return appropriate results.
/// </remarks>
public IList<McpRequestFilter<GetPromptRequestParams, GetPromptResult>> GetPromptFilters { get; } = [];
/// <summary>
/// Gets the filters for the list-resource-templates handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that return a list of available resource templates when requested by a client.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesTemplatesList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more resource templates.
/// </remarks>
public IList<McpRequestFilter<ListResourceTemplatesRequestParams, ListResourceTemplatesResult>> ListResourceTemplatesFilters { get; } = [];
/// <summary>
/// Gets the filters for the list-resources handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that return a list of available resources when requested by a client.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more resources.
/// </remarks>
public IList<McpRequestFilter<ListResourcesRequestParams, ListResourcesResult>> ListResourcesFilters { get; } = [];
/// <summary>
/// Gets the filters for the read-resource handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that are invoked when a client requests the content of a specific resource identified by its URI.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesRead"/> requests. The handler should implement logic to locate and retrieve the requested resource.
/// </remarks>
public IList<McpRequestFilter<ReadResourceRequestParams, ReadResourceResult>> ReadResourceFilters { get; } = [];
/// <summary>
/// Gets the filters for the complete-handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that provide auto-completion suggestions for prompt arguments or resource references in the Model Context Protocol.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.CompletionComplete"/> requests. The handler processes auto-completion requests, returning a list of suggestions based on the
/// reference type and current argument value.
/// </remarks>
public IList<McpRequestFilter<CompleteRequestParams, CompleteResult>> CompleteFilters { get; } = [];
/// <summary>
/// Gets the filters for the subscribe-to-resources handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that are invoked when a client wants to receive notifications about changes to specific resources or resource patterns.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesSubscribe"/> requests. The handler should implement logic to register the client's interest in the specified resources
/// and set up the necessary infrastructure to send notifications when those resources change.
/// </para>
/// <para>
/// After a successful subscription, the server should send resource change notifications to the client
/// whenever a relevant resource is created, updated, or deleted.
/// </para>
/// </remarks>
public IList<McpRequestFilter<SubscribeRequestParams, EmptyResult>> SubscribeToResourcesFilters { get; } = [];
/// <summary>
/// Gets the filters for the unsubscribe-from-resources handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that are invoked when a client wants to stop receiving notifications about previously subscribed resources.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesUnsubscribe"/> requests. The handler should implement logic to remove the client's subscriptions to the specified resources
/// and clean up any associated resources.
/// </para>
/// <para>
/// After a successful unsubscription, the server should no longer send resource change notifications
/// to the client for the specified resources.
/// </para>
/// </remarks>
public IList<McpRequestFilter<UnsubscribeRequestParams, EmptyResult>> UnsubscribeFromResourcesFilters { get; } = [];
/// <summary>
/// Gets the filters for the set-logging-level handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that process <see cref="RequestMethods.LoggingSetLevel"/> requests from clients. When set, it enables
/// clients to control which log messages they receive by specifying a minimum severity threshold.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.LoggingSetLevel"/> requests.
/// </para>
/// <para>
/// After handling a level change request, the server typically begins sending log messages
/// at or above the specified level to the client as notifications/message notifications.
/// </para>
/// </remarks>
public IList<McpRequestFilter<SetLevelRequestParams, EmptyResult>> SetLoggingLevelFilters { get; } = [];
}

179
src/ModelContextProtocol.Core/Server/McpServerFilters.cs
View file

@ -12,183 +12,12 @@ namespace ModelContextProtocol.Server;
public sealed class McpServerFilters
{
/// <summary>
/// Gets the filters for all incoming JSON-RPC messages.
/// Gets the filters for incoming and outgoing JSON-RPC messages.
/// </summary>
/// <remarks>
/// <para>
/// These filters intercept all incoming JSON-RPC messages before they are processed by the server,
/// including requests, notifications, responses, and errors. The filters can perform logging,
/// authentication, rate limiting, or other cross-cutting concerns that apply to all message types.
/// </para>
/// <para>
/// Message filters are applied before request-specific filters. If a message filter does not call
/// the next handler in the pipeline, the default handlers will not be executed.
/// </para>
/// </remarks>
public List<McpMessageFilter> IncomingMessageFilters { get; } = [];
public McpMessageFilters Message { get; } = new();
/// <summary>
/// Gets the filters for all outgoing JSON-RPC messages.
/// Gets the filters for request-specific MCP handler pipelines.
/// </summary>
/// <remarks>
/// <para>
/// These filters intercept all outgoing JSON-RPC messages before they are sent to the client,
/// including responses, notifications, and errors. The filters can perform logging,
/// redaction, auditing, or other cross-cutting concerns that apply to all message types.
/// </para>
/// <para>
/// If a message filter does not call the next handler in the pipeline, the message will not be sent.
/// Filters may also call the next handler multiple times with different messages to emit additional
/// server-to-client messages.
/// </para>
/// </remarks>
public List<McpMessageFilter> OutgoingMessageFilters { get; } = [];
/// <summary>
/// Gets the filters for the list-tools handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that return a list of available tools when requested by a client.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ToolsList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more tools.
/// </para>
/// <para>
/// These filters work alongside any tools defined in the <see cref="McpServerTool"/> collection.
/// Tools from both sources will be combined when returning results to clients.
/// </para>
/// </remarks>
public List<McpRequestFilter<ListToolsRequestParams, ListToolsResult>> ListToolsFilters { get; } = [];
/// <summary>
/// Gets the filters for the call-tool handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that are invoked when a client makes a call to a tool that isn't found in the <see cref="McpServerTool"/> collection.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ToolsCall"/> requests. The handler should implement logic to execute the requested tool and return appropriate results.
/// </remarks>
public List<McpRequestFilter<CallToolRequestParams, CallToolResult>> CallToolFilters { get; } = [];
/// <summary>
/// Gets the filters for the list-prompts handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that return a list of available prompts when requested by a client.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.PromptsList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more prompts.
/// </para>
/// <para>
/// These filters work alongside any prompts defined in the <see cref="McpServerPrompt"/> collection.
/// Prompts from both sources will be combined when returning results to clients.
/// </para>
/// </remarks>
public List<McpRequestFilter<ListPromptsRequestParams, ListPromptsResult>> ListPromptsFilters { get; } = [];
/// <summary>
/// Gets the filters for the get-prompt handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that are invoked when a client requests details for a specific prompt that isn't found in the <see cref="McpServerPrompt"/> collection.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.PromptsGet"/> requests. The handler should implement logic to fetch or generate the requested prompt and return appropriate results.
/// </remarks>
public List<McpRequestFilter<GetPromptRequestParams, GetPromptResult>> GetPromptFilters { get; } = [];
/// <summary>
/// Gets the filters for the list-resource-templates handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that return a list of available resource templates when requested by a client.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesTemplatesList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more resource templates.
/// </remarks>
public List<McpRequestFilter<ListResourceTemplatesRequestParams, ListResourceTemplatesResult>> ListResourceTemplatesFilters { get; } = [];
/// <summary>
/// Gets the filters for the list-resources handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that return a list of available resources when requested by a client.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more resources.
/// </remarks>
public List<McpRequestFilter<ListResourcesRequestParams, ListResourcesResult>> ListResourcesFilters { get; } = [];
/// <summary>
/// Gets the filters for the read-resource handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that are invoked when a client requests the content of a specific resource identified by its URI.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesRead"/> requests. The handler should implement logic to locate and retrieve the requested resource.
/// </remarks>
public List<McpRequestFilter<ReadResourceRequestParams, ReadResourceResult>> ReadResourceFilters { get; } = [];
/// <summary>
/// Gets the filters for the complete-handler pipeline.
/// </summary>
/// <remarks>
/// These filters wrap handlers that provide auto-completion suggestions for prompt arguments or resource references in the Model Context Protocol.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.CompletionComplete"/> requests. The handler processes auto-completion requests, returning a list of suggestions based on the
/// reference type and current argument value.
/// </remarks>
public List<McpRequestFilter<CompleteRequestParams, CompleteResult>> CompleteFilters { get; } = [];
/// <summary>
/// Gets the filters for the subscribe-to-resources handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that are invoked when a client wants to receive notifications about changes to specific resources or resource patterns.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesSubscribe"/> requests. The handler should implement logic to register the client's interest in the specified resources
/// and set up the necessary infrastructure to send notifications when those resources change.
/// </para>
/// <para>
/// After a successful subscription, the server should send resource change notifications to the client
/// whenever a relevant resource is created, updated, or deleted.
/// </para>
/// </remarks>
public List<McpRequestFilter<SubscribeRequestParams, EmptyResult>> SubscribeToResourcesFilters { get; } = [];
/// <summary>
/// Gets the filters for the unsubscribe-from-resources handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that are invoked when a client wants to stop receiving notifications about previously subscribed resources.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesUnsubscribe"/> requests. The handler should implement logic to remove the client's subscriptions to the specified resources
/// and clean up any associated resources.
/// </para>
/// <para>
/// After a successful unsubscription, the server should no longer send resource change notifications
/// to the client for the specified resources.
/// </para>
/// </remarks>
public List<McpRequestFilter<UnsubscribeRequestParams, EmptyResult>> UnsubscribeFromResourcesFilters { get; } = [];
/// <summary>
/// Gets the filters for the set-logging-level handler pipeline.
/// </summary>
/// <remarks>
/// <para>
/// These filters wrap handlers that process <see cref="RequestMethods.LoggingSetLevel"/> requests from clients. When set, it enables
/// clients to control which log messages they receive by specifying a minimum severity threshold.
/// The filters can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.LoggingSetLevel"/> requests.
/// </para>
/// <para>
/// After handling a level change request, the server typically begins sending log messages
/// at or above the specified level to the client as notifications/message notifications.
/// </para>
/// </remarks>
public List<McpRequestFilter<SetLevelRequestParams, EmptyResult>> SetLoggingLevelFilters { get; } = [];
public McpRequestFilters Request { get; } = new();
}

30
src/ModelContextProtocol.Core/Server/McpServerImpl.cs
View file

@ -119,8 +119,8 @@ internal sealed partial class McpServerImpl : McpServer
}
// And initialize the session.
var incomingMessageFilter = BuildMessageFilterPipeline(options.Filters.IncomingMessageFilters);
var outgoingMessageFilter = BuildMessageFilterPipeline(options.Filters.OutgoingMessageFilters);
var incomingMessageFilter = BuildMessageFilterPipeline(options.Filters.Message.IncomingFilters);
var outgoingMessageFilter = BuildMessageFilterPipeline(options.Filters.Message.OutgoingFilters);
_sessionHandler = new McpSessionHandler(
isServer: true,
_sessionTransport,
@ -260,7 +260,7 @@ internal sealed partial class McpServerImpl : McpServer
}
completeHandler ??= (static async (_, __) => new CompleteResult());
completeHandler = BuildFilterPipeline(completeHandler, options.Filters.CompleteFilters);
completeHandler = BuildFilterPipeline(completeHandler, options.Filters.Request.CompleteFilters);
ServerCapabilities.Completions = new();
@ -366,9 +366,9 @@ internal sealed partial class McpServerImpl : McpServer
// subscribe = true;
}
listResourcesHandler = BuildFilterPipeline(listResourcesHandler, options.Filters.ListResourcesFilters);
listResourceTemplatesHandler = BuildFilterPipeline(listResourceTemplatesHandler, options.Filters.ListResourceTemplatesFilters);
readResourceHandler = BuildFilterPipeline(readResourceHandler, options.Filters.ReadResourceFilters, handler =>
listResourcesHandler = BuildFilterPipeline(listResourcesHandler, options.Filters.Request.ListResourcesFilters);
listResourceTemplatesHandler = BuildFilterPipeline(listResourceTemplatesHandler, options.Filters.Request.ListResourceTemplatesFilters);
readResourceHandler = BuildFilterPipeline(readResourceHandler, options.Filters.Request.ReadResourceFilters, handler =>
async (request, cancellationToken) =>
{
// Initial handler that sets MatchedPrimitive
@ -405,8 +405,8 @@ internal sealed partial class McpServerImpl : McpServer
throw;
}
});
subscribeHandler = BuildFilterPipeline(subscribeHandler, options.Filters.SubscribeToResourcesFilters);
unsubscribeHandler = BuildFilterPipeline(unsubscribeHandler, options.Filters.UnsubscribeFromResourcesFilters);
subscribeHandler = BuildFilterPipeline(subscribeHandler, options.Filters.Request.SubscribeToResourcesFilters);
unsubscribeHandler = BuildFilterPipeline(unsubscribeHandler, options.Filters.Request.UnsubscribeFromResourcesFilters);
ServerCapabilities.Resources.ListChanged = listChanged;
ServerCapabilities.Resources.Subscribe = subscribe;
@ -496,8 +496,8 @@ internal sealed partial class McpServerImpl : McpServer
listChanged = true;
}
listPromptsHandler = BuildFilterPipeline(listPromptsHandler, options.Filters.ListPromptsFilters);
getPromptHandler = BuildFilterPipeline(getPromptHandler, options.Filters.GetPromptFilters, handler =>
listPromptsHandler = BuildFilterPipeline(listPromptsHandler, options.Filters.Request.ListPromptsFilters);
getPromptHandler = BuildFilterPipeline(getPromptHandler, options.Filters.Request.GetPromptFilters, handler =>
async (request, cancellationToken) =>
{
// Initial handler that sets MatchedPrimitive
@ -618,8 +618,8 @@ internal sealed partial class McpServerImpl : McpServer
listChanged = true;
}
listToolsHandler = BuildFilterPipeline(listToolsHandler, options.Filters.ListToolsFilters);
callToolHandler = BuildFilterPipeline(callToolHandler, options.Filters.CallToolFilters, handler =>
listToolsHandler = BuildFilterPipeline(listToolsHandler, options.Filters.Request.ListToolsFilters);
callToolHandler = BuildFilterPipeline(callToolHandler, options.Filters.Request.CallToolFilters, handler =>
async (request, cancellationToken) =>
{
// Initial handler that sets MatchedPrimitive
@ -819,7 +819,7 @@ internal sealed partial class McpServerImpl : McpServer
// Apply filters to the handler
if (setLoggingLevelHandler is not null)
{
setLoggingLevelHandler = BuildFilterPipeline(setLoggingLevelHandler, options.Filters.SetLoggingLevelFilters);
setLoggingLevelHandler = BuildFilterPipeline(setLoggingLevelHandler, options.Filters.Request.SetLoggingLevelFilters);
}
ServerCapabilities.Logging = new();
@ -903,7 +903,7 @@ internal sealed partial class McpServerImpl : McpServer
private static McpRequestHandler<TParams, TResult> BuildFilterPipeline<TParams, TResult>(
McpRequestHandler<TParams, TResult> baseHandler,
List<McpRequestFilter<TParams, TResult>> filters,
IList<McpRequestFilter<TParams, TResult>> filters,
McpRequestFilter<TParams, TResult>? initialHandler = null)
{
var current = baseHandler;
@ -921,7 +921,7 @@ internal sealed partial class McpServerImpl : McpServer
return current;
}
private JsonRpcMessageFilter BuildMessageFilterPipeline(List<McpMessageFilter> filters)
private JsonRpcMessageFilter BuildMessageFilterPipeline(IList<McpMessageFilter> filters)
{
if (filters.Count == 0)
{

22
src/ModelContextProtocol.Core/Server/McpServerOptions.cs
View file

@ -94,29 +94,21 @@ public sealed class McpServerOptions
/// </remarks>
public ClientCapabilities? KnownClientCapabilities { get; set; }
/// <summary>
/// Gets or sets the container of handlers used by the server for processing protocol messages.
/// </summary>
public McpServerHandlers Handlers { get; } = new();
/// <summary>
/// Gets the filter collections for MCP server handlers.
/// </summary>
/// <remarks>
/// This property provides access to filter collections that can be used to modify the behavior
/// of various MCP server handlers. Filters are applied in reverse order, so the last filter
/// added will be the outermost (first to execute).
/// of various MCP server handlers. The first filter added is the outermost (first to execute),
/// and each subsequent filter wraps closer to the handler.
/// </remarks>
public McpServerFilters Filters { get; } = new();
/// <summary>
/// Gets or sets the container of handlers used by the server for processing protocol messages.
/// </summary>
public McpServerHandlers Handlers
{
get => field ??= new();
set
{
Throw.IfNull(value);
field = value;
}
}
/// <summary>
/// Gets or sets a collection of tools served by the server.
/// </summary>

3
src/ModelContextProtocol.Core/Server/MessageContext.cs
View file

@ -14,7 +14,8 @@ namespace ModelContextProtocol.Server;
/// </para>
/// <para>
/// This type is typically received as a parameter in message filter delegates registered via
/// <see cref="McpServerFilters.IncomingMessageFilters"/> or <see cref="McpServerFilters.OutgoingMessageFilters"/>.
/// <see cref="McpServerFilters.Message"/>'s <see cref="McpMessageFilters.IncomingFilters"/> or
/// <see cref="McpMessageFilters.OutgoingFilters"/> collections.
/// </para>
/// </remarks>
public class MessageContext

6
src/ModelContextProtocol/DefaultMcpMessageFilterBuilder.cs Normal file
View file

@ -0,0 +1,6 @@
namespace Microsoft.Extensions.DependencyInjection;
internal sealed class DefaultMcpMessageFilterBuilder(IMcpServerBuilder serverBuilder) : IMcpMessageFilterBuilder
{
public IServiceCollection Services { get; } = serverBuilder.Services;
}

6
src/ModelContextProtocol/DefaultMcpRequestFilterBuilder.cs Normal file
View file

@ -0,0 +1,6 @@
namespace Microsoft.Extensions.DependencyInjection;
internal sealed class DefaultMcpRequestFilterBuilder(IMcpServerBuilder serverBuilder) : IMcpRequestFilterBuilder
{
public IServiceCollection Services { get; } = serverBuilder.Services;
}

14
src/ModelContextProtocol/IMcpMessageFilterBuilder.cs Normal file
View file

@ -0,0 +1,14 @@
using ModelContextProtocol.Server;
namespace Microsoft.Extensions.DependencyInjection;
/// <summary>
/// Provides a builder for configuring message-level MCP server filters.
/// </summary>
public interface IMcpMessageFilterBuilder
{
/// <summary>
/// Gets the associated service collection.
/// </summary>
IServiceCollection Services { get; }
}

14
src/ModelContextProtocol/IMcpRequestFilterBuilder.cs Normal file
View file

@ -0,0 +1,14 @@
using ModelContextProtocol.Server;
namespace Microsoft.Extensions.DependencyInjection;
/// <summary>
/// Provides a builder for configuring request-specific MCP server filters.
/// </summary>
public interface IMcpRequestFilterBuilder
{
/// <summary>
/// Gets the associated service collection.
/// </summary>
IServiceCollection Services { get; }
}

40
src/ModelContextProtocol/McpMessageFilterBuilderExtensions.cs Normal file
View file

@ -0,0 +1,40 @@
using ModelContextProtocol;
using ModelContextProtocol.Server;
namespace Microsoft.Extensions.DependencyInjection;
/// <summary>
/// Provides extension methods for configuring message-level MCP server filters.
/// </summary>
public static class McpMessageFilterBuilderExtensions
{
/// <summary>
/// Adds a filter to intercept all incoming JSON-RPC messages.
/// </summary>
/// <param name="builder">The message filter builder instance.</param>
/// <param name="filter">The filter function that wraps the message handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpMessageFilterBuilder AddIncomingFilter(this IMcpMessageFilterBuilder builder, McpMessageFilter filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Message.IncomingFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to intercept all outgoing JSON-RPC messages.
/// </summary>
/// <param name="builder">The message filter builder instance.</param>
/// <param name="filter">The filter function that wraps the message handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpMessageFilterBuilder AddOutgoingFilter(this IMcpMessageFilterBuilder builder, McpMessageFilter filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Message.OutgoingFilters.Add(filter));
return builder;
}
}

176
src/ModelContextProtocol/McpRequestFilterBuilderExtensions.cs Normal file
View file

@ -0,0 +1,176 @@
using ModelContextProtocol;
using ModelContextProtocol.Protocol;
using ModelContextProtocol.Server;
namespace Microsoft.Extensions.DependencyInjection;
/// <summary>
/// Provides extension methods for configuring request-specific MCP server filters.
/// </summary>
public static class McpRequestFilterBuilderExtensions
{
/// <summary>
/// Adds a filter to the list resource templates handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddListResourceTemplatesFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<ListResourceTemplatesRequestParams, ListResourceTemplatesResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.ListResourceTemplatesFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the list tools handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddListToolsFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<ListToolsRequestParams, ListToolsResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.ListToolsFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the call tool handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddCallToolFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<CallToolRequestParams, CallToolResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.CallToolFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the list prompts handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddListPromptsFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<ListPromptsRequestParams, ListPromptsResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.ListPromptsFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the get prompt handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddGetPromptFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<GetPromptRequestParams, GetPromptResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.GetPromptFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the list resources handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddListResourcesFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<ListResourcesRequestParams, ListResourcesResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.ListResourcesFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the read resource handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddReadResourceFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<ReadResourceRequestParams, ReadResourceResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.ReadResourceFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the complete handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddCompleteFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<CompleteRequestParams, CompleteResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.CompleteFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the subscribe-to-resources handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddSubscribeToResourcesFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<SubscribeRequestParams, EmptyResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.SubscribeToResourcesFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the unsubscribe-from-resources handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddUnsubscribeFromResourcesFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<UnsubscribeRequestParams, EmptyResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.UnsubscribeFromResourcesFilters.Add(filter));
return builder;
}
/// <summary>
/// Adds a filter to the set logging level handler pipeline.
/// </summary>
/// <param name="builder">The request filter builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
public static IMcpRequestFilterBuilder AddSetLoggingLevelFilter(this IMcpRequestFilterBuilder builder, McpRequestFilter<SetLevelRequestParams, EmptyResult> filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.Request.SetLoggingLevelFilters.Add(filter));
return builder;
}
}

316
src/ModelContextProtocol/McpServerBuilderExtensions.cs
View file

@ -893,28 +893,49 @@ public static partial class McpServerBuilderExtensions
#endregion
#region Filters
/// <summary>
/// Configures message-level filters for the MCP server.
/// </summary>
/// <param name="builder">The builder instance.</param>
/// <param name="configure">A callback used to register message filters.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> or <paramref name="configure"/> is <see langword="null"/>.</exception>
public static IMcpServerBuilder WithMessageFilters(this IMcpServerBuilder builder, Action<IMcpMessageFilterBuilder> configure)
{
Throw.IfNull(builder);
Throw.IfNull(configure);
configure(new DefaultMcpMessageFilterBuilder(builder));
return builder;
}
/// <summary>
/// Configures request-specific filters for the MCP server.
/// </summary>
/// <param name="builder">The builder instance.</param>
/// <param name="configure">A callback used to register request-specific filters.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> or <paramref name="configure"/> is <see langword="null"/>.</exception>
public static IMcpServerBuilder WithRequestFilters(this IMcpServerBuilder builder, Action<IMcpRequestFilterBuilder> configure)
{
Throw.IfNull(builder);
Throw.IfNull(configure);
configure(new DefaultMcpRequestFilterBuilder(builder));
return builder;
}
#pragma warning disable CS0436 // ObsoleteAttribute polyfill conflicts with framework type on netstandard.
/// <summary>
/// Adds a filter to the list resource templates handler pipeline.
/// </summary>
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that return a list of available resource templates when requested by a client.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesTemplatesList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more resource templates.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddListResourceTemplatesFilter(this IMcpServerBuilder builder, McpRequestFilter<ListResourceTemplatesRequestParams, ListResourceTemplatesResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.ListResourceTemplatesFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddListResourceTemplatesFilter(this IMcpServerBuilder builder, McpRequestFilter<ListResourceTemplatesRequestParams, ListResourceTemplatesResult> filter) =>
builder.WithRequestFilters(filters => filters.AddListResourceTemplatesFilter(filter));
/// <summary>
/// Adds a filter to the list tools handler pipeline.
@ -922,26 +943,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that return a list of available tools when requested by a client.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ToolsList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more tools.
/// </para>
/// <para>
/// This filter works alongside any tools defined in the <see cref="McpServerTool"/> collection.
/// Tools from both sources will be combined when returning results to clients.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddListToolsFilter(this IMcpServerBuilder builder, McpRequestFilter<ListToolsRequestParams, ListToolsResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.ListToolsFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddListToolsFilter(this IMcpServerBuilder builder, McpRequestFilter<ListToolsRequestParams, ListToolsResult> filter) =>
builder.WithRequestFilters(filters => filters.AddListToolsFilter(filter));
/// <summary>
/// Adds a filter to the call tool handler pipeline.
@ -949,21 +953,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that are invoked when a client makes a call to a tool that isn't found in the <see cref="McpServerTool"/> collection.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ToolsCall"/> requests. The handler should implement logic to execute the requested tool and return appropriate results.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddCallToolFilter(this IMcpServerBuilder builder, McpRequestFilter<CallToolRequestParams, CallToolResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.CallToolFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddCallToolFilter(this IMcpServerBuilder builder, McpRequestFilter<CallToolRequestParams, CallToolResult> filter) =>
builder.WithRequestFilters(filters => filters.AddCallToolFilter(filter));
/// <summary>
/// Adds a filter to the list prompts handler pipeline.
@ -971,26 +963,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that return a list of available prompts when requested by a client.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.PromptsList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more prompts.
/// </para>
/// <para>
/// This filter works alongside any prompts defined in the <see cref="McpServerPrompt"/> collection.
/// Prompts from both sources will be combined when returning results to clients.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddListPromptsFilter(this IMcpServerBuilder builder, McpRequestFilter<ListPromptsRequestParams, ListPromptsResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.ListPromptsFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddListPromptsFilter(this IMcpServerBuilder builder, McpRequestFilter<ListPromptsRequestParams, ListPromptsResult> filter) =>
builder.WithRequestFilters(filters => filters.AddListPromptsFilter(filter));
/// <summary>
/// Adds a filter to the get prompt handler pipeline.
@ -998,21 +973,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that are invoked when a client requests details for a specific prompt that isn't found in the <see cref="McpServerPrompt"/> collection.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.PromptsGet"/> requests. The handler should implement logic to fetch or generate the requested prompt and return appropriate results.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddGetPromptFilter(this IMcpServerBuilder builder, McpRequestFilter<GetPromptRequestParams, GetPromptResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.GetPromptFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddGetPromptFilter(this IMcpServerBuilder builder, McpRequestFilter<GetPromptRequestParams, GetPromptResult> filter) =>
builder.WithRequestFilters(filters => filters.AddGetPromptFilter(filter));
/// <summary>
/// Adds a filter to the list resources handler pipeline.
@ -1020,22 +983,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that return a list of available resources when requested by a client.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesList"/> requests. It supports pagination through the cursor mechanism,
/// where the client can make repeated calls with the cursor returned by the previous call to retrieve more resources.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddListResourcesFilter(this IMcpServerBuilder builder, McpRequestFilter<ListResourcesRequestParams, ListResourcesResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.ListResourcesFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddListResourcesFilter(this IMcpServerBuilder builder, McpRequestFilter<ListResourcesRequestParams, ListResourcesResult> filter) =>
builder.WithRequestFilters(filters => filters.AddListResourcesFilter(filter));
/// <summary>
/// Adds a filter to the read resource handler pipeline.
@ -1043,21 +993,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that are invoked when a client requests the content of a specific resource identified by its URI.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesRead"/> requests. The handler should implement logic to locate and retrieve the requested resource.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddReadResourceFilter(this IMcpServerBuilder builder, McpRequestFilter<ReadResourceRequestParams, ReadResourceResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.ReadResourceFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddReadResourceFilter(this IMcpServerBuilder builder, McpRequestFilter<ReadResourceRequestParams, ReadResourceResult> filter) =>
builder.WithRequestFilters(filters => filters.AddReadResourceFilter(filter));
/// <summary>
/// Adds a filter to the complete handler pipeline.
@ -1065,22 +1003,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that provide auto-completion suggestions for prompt arguments or resource references in the Model Context Protocol.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.CompletionComplete"/> requests. The handler processes auto-completion requests, returning a list of suggestions based on the
/// reference type and current argument value.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddCompleteFilter(this IMcpServerBuilder builder, McpRequestFilter<CompleteRequestParams, CompleteResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.CompleteFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddCompleteFilter(this IMcpServerBuilder builder, McpRequestFilter<CompleteRequestParams, CompleteResult> filter) =>
builder.WithRequestFilters(filters => filters.AddCompleteFilter(filter));
/// <summary>
/// Adds a filter to the subscribe-to-resources handler pipeline.
@ -1088,26 +1013,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that are invoked when a client wants to receive notifications about changes to specific resources or resource patterns.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesSubscribe"/> requests. The handler should implement logic to register the client's interest in the specified resources
/// and set up the necessary infrastructure to send notifications when those resources change.
/// </para>
/// <para>
/// After a successful subscription, the server should send resource change notifications to the client
/// whenever a relevant resource is created, updated, or deleted.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddSubscribeToResourcesFilter(this IMcpServerBuilder builder, McpRequestFilter<SubscribeRequestParams, EmptyResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.SubscribeToResourcesFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddSubscribeToResourcesFilter(this IMcpServerBuilder builder, McpRequestFilter<SubscribeRequestParams, EmptyResult> filter) =>
builder.WithRequestFilters(filters => filters.AddSubscribeToResourcesFilter(filter));
/// <summary>
/// Adds a filter to the unsubscribe-from-resources handler pipeline.
@ -1115,26 +1023,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that are invoked when a client wants to stop receiving notifications about previously subscribed resources.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.ResourcesUnsubscribe"/> requests. The handler should implement logic to remove the client's subscriptions to the specified resources
/// and clean up any associated resources.
/// </para>
/// <para>
/// After a successful unsubscription, the server should no longer send resource change notifications
/// to the client for the specified resources.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddUnsubscribeFromResourcesFilter(this IMcpServerBuilder builder, McpRequestFilter<UnsubscribeRequestParams, EmptyResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.UnsubscribeFromResourcesFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddUnsubscribeFromResourcesFilter(this IMcpServerBuilder builder, McpRequestFilter<UnsubscribeRequestParams, EmptyResult> filter) =>
builder.WithRequestFilters(filters => filters.AddUnsubscribeFromResourcesFilter(filter));
/// <summary>
/// Adds a filter to the set logging level handler pipeline.
@ -1142,26 +1033,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter wraps handlers that process <see cref="RequestMethods.LoggingSetLevel"/> requests from clients. When set, it enables
/// clients to control which log messages they receive by specifying a minimum severity threshold.
/// The filter can modify, log, or perform additional operations on requests and responses for
/// <see cref="RequestMethods.LoggingSetLevel"/> requests.
/// </para>
/// <para>
/// After handling a level change request, the server typically begins sending log messages
/// at or above the specified level to the client as notifications or message notifications.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddSetLoggingLevelFilter(this IMcpServerBuilder builder, McpRequestFilter<SetLevelRequestParams, EmptyResult> filter)
{
Throw.IfNull(builder);
builder.Services.Configure<McpServerOptions>(options => options.Filters.SetLoggingLevelFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.RequestFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddSetLoggingLevelFilter(this IMcpServerBuilder builder, McpRequestFilter<SetLevelRequestParams, EmptyResult> filter) =>
builder.WithRequestFilters(filters => filters.AddSetLoggingLevelFilter(filter));
/// <summary>
/// Adds a filter to intercept all incoming JSON-RPC messages.
@ -1169,36 +1043,9 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the message handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter intercepts all incoming JSON-RPC messages before they are processed by the server,
/// including requests, notifications, responses, and errors. The filter can perform logging,
/// authentication, rate limiting, or other cross-cutting concerns that apply to all message types.
/// </para>
/// <para>
/// Message filters are applied before request-specific filters. If a message filter does not call
/// the next handler in the pipeline, the default handlers will not be executed.
/// </para>
/// <para>
/// Filters are applied in the order they are registered, with the first registered filter being the outermost.
/// Each filter receives the next handler in the pipeline and can choose to:
/// <list type="bullet">
/// <item><description>Call the next handler to continue processing: <c>await next(context, cancellationToken)</c></description></item>
/// <item><description>Skip the default handlers entirely by not calling next</description></item>
/// <item><description>Perform operations before and/or after calling next</description></item>
/// <item><description>Catch and handle exceptions from inner handlers</description></item>
/// </list>
/// </para>
/// </remarks>
public static IMcpServerBuilder AddIncomingMessageFilter(this IMcpServerBuilder builder, McpMessageFilter filter)
{
Throw.IfNull(builder);
Throw.IfNull(filter);
builder.Services.Configure<McpServerOptions>(options => options.Filters.IncomingMessageFilters.Add(filter));
return builder;
}
[Obsolete(Obsoletions.MessageFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddIncomingMessageFilter(this IMcpServerBuilder builder, McpMessageFilter filter) =>
builder.WithMessageFilters(filters => filters.AddIncomingFilter(filter));
/// <summary>
/// Adds a filter to intercept all outgoing JSON-RPC messages.
@ -1206,26 +1053,11 @@ public static partial class McpServerBuilderExtensions
/// <param name="builder">The builder instance.</param>
/// <param name="filter">The filter function that wraps the message handler.</param>
/// <returns>The builder provided in <paramref name="builder"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="builder"/> is <see langword="null"/>.</exception>
/// <remarks>
/// <para>
/// This filter intercepts all outgoing JSON-RPC messages before they are sent to the client,
/// including responses, notifications, and errors. The filter can perform logging, redaction,
/// auditing, or other cross-cutting concerns that apply to all message types.
/// </para>
/// <para>
/// If a message filter does not call the next handler in the pipeline, the message will not be sent.
/// Filters may also call the next handler multiple times with different messages to emit additional
/// server-to-client messages.
/// </para>
/// </remarks>
public static IMcpServerBuilder AddOutgoingMessageFilter(this IMcpServerBuilder builder, McpMessageFilter filter)
{
Throw.IfNull(builder);
[Obsolete(Obsoletions.MessageFilter_Message, DiagnosticId = Obsoletions.MessageAndRequestFilter_DiagnosticId, UrlFormat = Obsoletions.MessageAndRequestFilter_Url)]
public static IMcpServerBuilder AddOutgoingMessageFilter(this IMcpServerBuilder builder, McpMessageFilter filter) =>
builder.WithMessageFilters(filters => filters.AddOutgoingFilter(filter));
builder.Services.Configure<McpServerOptions>(options => options.Filters.OutgoingMessageFilters.Add(filter));
return builder;
}
#pragma warning restore CS0436
#endregion
#region Transports

1
src/ModelContextProtocol/ModelContextProtocol.csproj
View file

@ -18,6 +18,7 @@
<ItemGroup>
<Compile Include="..\Common\Throw.cs" Link="Throw.cs" />
<Compile Include="..\Common\Obsoletions.cs" Link="Obsoletions.cs" />
</ItemGroup>
<ItemGroup>