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Add doc with sample on accessing HttpContext
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‎ModelContextProtocol.slnx‎

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<Folder Name="/docs/concepts/elicitation/samples/server/">
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<Project Path="docs/concepts/elicitation/samples/server/Elicitation.csproj" />
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</Folder>
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<Folder Name="/docs/concepts/httpcontext/" />
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<Folder Name="/docs/concepts/httpcontext/samples/">
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<Project Path="docs/concepts/httpcontext/samples/HttpContext.csproj" />
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</Folder>
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<Folder Name="/docs/concepts/logging/" />
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<Folder Name="/docs/concepts/logging/samples/" />
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<Folder Name="/docs/concepts/logging/samples/client/">

‎docs/concepts/httpcontext/httpcontext.md‎

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---
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title: HTTP Context
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author: mikekistler
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description: How to use the logging feature in the MCP C# SDK.
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uid: httpcontext
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---
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## HTTP Context
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When using the Streamable HTTP transport, an MCP server may need to access the underlying [HttpContext] for a request.
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The [HttpContext] contains request metadata such as the HTTP headers, authorization context, and the actual path and query string for the request.
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To access the [HttpContext], the MCP server should add the [IHttpContextAccessor] service to the application service collection (typically in Program.cs).
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Then any classes, e.g. a class containing MCP tools, should accept an [IHttpContextAccessor] in their constructor and store this for use by its methods.
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Methods then use the [HttpContext property][IHttpContextAccessor.HttpContext] of the accessor to get the current context.
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[HttpContext]: https://learn.microsoft.com/dotnet/api/microsoft.aspnetcore.http.httpcontext
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[IHttpContextAccessor]: https://learn.microsoft.com/dotnet/api/microsoft.aspnetcore.http.ihttpcontextaccessor
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[IHttpContextAccessor.HttpContext]: https://learn.microsoft.com/dotnet/api/microsoft.aspnetcore.http.ihttpcontextaccessor.httpcontext
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The following code snippet illustrates how to add the [IHttpContextAccessor] service to the application service collection:
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[!code-csharp[](samples/Program.cs?name=snippet_AddHttpContextAccessor)]
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If `ContextTools` is a class whose methods need access to the [HttpContext], the following snippet shows how it can accept
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an [IHttpContextAccessor] in its constructor and store it for later use:
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[!code-csharp[](samples/Tools/ContextTools.cs?name=snippet_ConstructorParameter)]
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A method of `ContextTools` can then access the current [HttpContext] as follows:
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<!-- highlight the last 5 lines -->
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[!code-csharp[](samples/Tools/ContextTools.cs?name=snippet_AccessHttpContext)]
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### Complete example
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A complete example of an MCP Server that uses this method to access the [HttpContext] within tool methods is available
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in [this sample project](https://github.com/mikekistler/mcp-howto/tree/main/HttpContext).
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You can run the project and then use the [TryItOut notebook](./samples/TryItOut.ipynb) to call one of the tools
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that access the HTTP context and returns the HTTP headers as a JSON object.

‎docs/concepts/httpcontext/samples/HttpContext.csproj‎

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<Project Sdk="Microsoft.NET.Sdk.Web">
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<PropertyGroup>
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<TargetFramework>net9.0</TargetFramework>
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<Nullable>enable</Nullable>
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<ImplicitUsings>enable</ImplicitUsings>
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</PropertyGroup>
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<ItemGroup>
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<ProjectReference Include="../../../../src/ModelContextProtocol.AspNetCore/ModelContextProtocol.AspNetCore.csproj" />
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</ItemGroup>
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</Project>

‎docs/concepts/httpcontext/samples/HttpContext.http‎

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@HostAddress = http://localhost:3001
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POST {{HostAddress}}/
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Accept: application/json, text/event-stream
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Content-Type: application/json
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MCP-Protocol-Version: 2025-06-18
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{
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"jsonrpc": "2.0",
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"id": 2,
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"method": "tools/call",
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"params": {
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"name": "get_http_headers"
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}
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}
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###
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POST {{HostAddress}}/
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Accept: application/json, text/event-stream
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Content-Type: application/json
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MCP-Protocol-Version: 2025-06-18
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{
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"jsonrpc": "2.0",
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"id": 2,
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"method": "tools/call",
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"params": {
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"name": "get_request_info"
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}
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}
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###
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POST {{HostAddress}}/
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Accept: application/json, text/event-stream
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Content-Type: application/json
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MCP-Protocol-Version: 2025-06-18
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{
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"jsonrpc": "2.0",
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"id": 2,
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"method": "tools/call",
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"params": {
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"name": "get_user_claims"
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}
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}

‎docs/concepts/httpcontext/samples/Program.cs‎

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using HttpContext.Tools;
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var builder = WebApplication.CreateBuilder(args);
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// Add services to the container.
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builder.Services.AddMcpServer()
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.WithHttpTransport()
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.WithTools<ContextTools>();
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// <snippet_AddHttpContextAccessor>
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builder.Services.AddHttpContextAccessor();
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// </snippet_AddHttpContextAccessor>
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builder.Logging.AddConsole(options =>
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{
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options.LogToStandardErrorThreshold = LogLevel.Information;
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});
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var app = builder.Build();
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app.UseHttpsRedirection();
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app.MapMcp();
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app.Run();

‎docs/concepts/httpcontext/samples/Properties/launchSettings.json‎

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{
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"$schema": "https://json.schemastore.org/launchsettings.json",
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"profiles": {
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"http": {
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"commandName": "Project",
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"dotnetRunMessages": true,
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"launchBrowser": false,
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"applicationUrl": "http://localhost:3001",
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"environmentVariables": {
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"ASPNETCORE_ENVIRONMENT": "Development"
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}
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},
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"https": {
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"commandName": "Project",
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"dotnetRunMessages": true,
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"launchBrowser": false,
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"applicationUrl": "https://localhost:7191;http://localhost:3001",
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"environmentVariables": {
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"ASPNETCORE_ENVIRONMENT": "Development"
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}
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}
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}
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}

‎docs/concepts/httpcontext/samples/Tools/ContextTools.cs‎

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using Microsoft.AspNetCore.Http;
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using ModelContextProtocol.Server;
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using System.ComponentModel;
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using System.Text.Json;
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namespace HttpContext.Tools;
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// <snippet_ConstructorParameter>
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public class ContextTools
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{
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private readonly IHttpContextAccessor _httpContextAccessor;
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public ContextTools(IHttpContextAccessor httpContextAccessor)
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{
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_httpContextAccessor = httpContextAccessor;
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}
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// remainder of ContextTools follows
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// </snippet_ConstructorParameter>
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// <snippet_AccessHttpContext>
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[McpServerTool(UseStructuredContent = true)]
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[Description("Retrieves the HTTP headers from the current request and returns them as a JSON object.")]
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public object GetHttpHeaders()
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{
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var context = _httpContextAccessor.HttpContext;
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if (context == null)
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{
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return "No HTTP context available";
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}
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// Remainder of GetHttpHeaders method follows
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// </snippet_AccessHttpContext>
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var headers = new Dictionary<string, string>();
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foreach (var header in context.Request.Headers)
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{
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headers[header.Key] = string.Join(", ", header.Value.ToArray());
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}
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return headers;
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}
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[McpServerTool(UseStructuredContent = true)]
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[Description("Retrieves the request information from the current HTTP context and returns it as structured content.")]
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public object GetRequestInfo()
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{
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var context = _httpContextAccessor.HttpContext;
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if (context == null)
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{
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return new { Error = "No HTTP context available" };
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}
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var requestInfo = new
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{
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context.Request.Method,
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Path = context.Request.Path.Value,
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QueryString = context.Request.QueryString.Value,
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context.Request.ContentType,
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UserAgent = context.Request.Headers.UserAgent.ToString(),
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RemoteIpAddress = context.Connection.RemoteIpAddress?.ToString(),
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context.Request.IsHttps
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};
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return requestInfo;
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}
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[McpServerTool(UseStructuredContent = true)]
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[Description("Retrieves the user claims from the current HTTP context and returns them as a JSON object.")]
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public object GetUserClaims()
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{
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var context = _httpContextAccessor.HttpContext;
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if (context == null)
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{
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return "No HTTP context available";
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}
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var claims = context.User.Claims.Select(c => new
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{
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c.Type,
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c.Value
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}).ToList();
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return claims;
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}
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}

‎docs/concepts/httpcontext/samples/TryItOut.ipynb‎

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{
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"cells": [
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{
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"cell_type": "markdown",
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"id": "37868ee2",
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"metadata": {
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"language_info": {
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"name": "polyglot-notebook"
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},
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"polyglot_notebook": {
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"kernelName": "csharp"
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}
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},
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"source": [
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"## HTTP Context\n",
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"\n",
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"This project illustrates how to access the HttpContext from tool calls. See the [README](../README.md) for more details.\n"
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]
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},
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{
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"cell_type": "markdown",
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"id": "093a7d4f",
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"metadata": {},
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"source": [
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"### Examples\n",
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"\n",
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"The following request illustrates a tool call that retrieves the HTTP headers from the [HttpContext] using the [IHttpContextAccessor].\n",
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"\n",
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"The server implements two other tools, `get_request_info` and `get_user_claims`. You can modify the code below to call these tools as well,\n",
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"which illustrate how to access other parts of the [HttpContext].\n",
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"\n",
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"```python\n",
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"\n",
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"[HttpContext]: https://docs.microsoft.com/dotnet/api/microsoft.aspnetcore.http.httpcontext\n",
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"[IHttpContextAccessor]: https://docs.microsoft.com/dotnet/api/microsoft.aspnetcore.http.ihttpcontextaccessor"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 4,
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"id": "3324ec56",
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"metadata": {
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"language_info": {
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"name": "polyglot-notebook"
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},
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"polyglot_notebook": {
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"kernelName": "pwsh"
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}
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},
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"outputs": [
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{
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"name": "stdout",
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"output_type": "stream",
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"text": [
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"{\n",
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" \"result\": {\n",
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" \"content\": [\n",
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" {\n",
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" \"type\": \"text\",\n",
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" \"text\": \"[]\"\n",
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" }\n",
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" ],\n",
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" \"structuredContent\": {\n",
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" \"result\": []\n",
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" }\n",
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" },\n",
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" \"id\": 1,\n",
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" \"jsonrpc\": \"2.0\"\n",
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"}\n"
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]
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}
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],
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"source": [
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"curl -s -X POST http://localhost:3001 `\n",
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"-H \"ProtocolVersion: 2025-06-18\" `\n",
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"-H \"Accept: application/json, text/event-stream\" `\n",
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"-H \"Content-Type: application/json\" `\n",
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"-d '{\n",
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" \"jsonrpc\": \"2.0\",\n",
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" \"id\": 1,\n",
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" \"method\": \"tools/call\",\n",
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" \"params\": {\n",
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" \"name\": \"get_user_claims\"\n",
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" }\n",
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"}' | Where-Object { $_ -like \"data:*\" } | ForEach-Object { $_.Substring(5) } | jq"
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]
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}
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],
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"metadata": {
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"kernelspec": {
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"display_name": ".NET (C#)",
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"language": "C#",
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"name": ".net-csharp"
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},
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"language_info": {
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"name": "polyglot-notebook"
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},
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"polyglot_notebook": {
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"kernelInfo": {
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"defaultKernelName": "csharp",
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"items": [
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{
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"aliases": [],
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"languageName": "csharp",
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"name": "csharp"
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}
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]
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}
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}
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},
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"nbformat": 4,
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"nbformat_minor": 5
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}

‎docs/concepts/httpcontext/samples/appsettings.Development.json‎

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{
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"Logging": {
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"LogLevel": {
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"Default": "Information",
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"Microsoft.AspNetCore": "Warning"
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}
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}
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}

‎docs/concepts/httpcontext/samples/appsettings.json‎

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{
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"Logging": {
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"LogLevel": {
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"Default": "Information",
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"Microsoft.AspNetCore": "Warning"
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}
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},
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"AllowedHosts": "*"
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}

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