✨ What is Mcp.Net?

Mcp.Net is a .NET implementation of the Model Context Protocol (MCP) - a standardized way for apps to talk to AI models and execute tools. Think of it as the "HTTP of AI tool usage" - a clean, consistent way for your app to give AI models the ability to:

• 🧰 Use tools like search, weather lookup, database access
• 🌐 Access web resources and fetch web content
• 📝 Work with predefined prompts and templates

⚠️ Pre-1.0 Notice

This is version 0.9.0 - the core is stable but some features are still in development. See Current Status for details.

🏃‍♀️ Quick Start

Try the interactive LLM demo

Experience MCP (with web-search, scraping, twilio, various demo tools) with OpenAI or Anthropic models in just two steps:

# 1. Start the server with demo tools
dotnet run --project Mcp.Net.Examples.SimpleServer/Mcp.Net.Examples.SimpleServer.csproj

# 2. In a new terminal, run the LLM chat app (requires OpenAI or Anthropic API key)
dotnet run --project Mcp.Net.LLM/Mcp.Net.LLM.csproj

See the LLM demo documentation for more details.

Install the packages

# For building a server (the thing that provides tools)
dotnet add package Mcp.Net.Server

# For building a client (the thing that talks to AI models)
dotnet add package Mcp.Net.Client

Run the sample server + client with OAuth 2.1

# Terminal 1 — start the demo server (SSE on http://localhost:5000)
dotnet run --project Mcp.Net.Examples.SimpleServer/Mcp.Net.Examples.SimpleServer.csproj

# Terminal 2 — launch the client (performs dynamic registration + PKCE)
dotnet run --project Mcp.Net.Examples.SimpleClient -- --url http://localhost:5000 --auth-mode pkce

ℹ️ The first SSE GET returns 401 Unauthorized by design. The client follows the WWW-Authenticate challenge, registers itself at /oauth/register, completes the PKCE handshake, and reconnects with a bearer token. Watch the logs to see resources, prompts, and tools (including the new elicitation flow) being exercised end-to-end. When the Warhammer inquisitor tool runs you’ll be prompted to accept/decline/cancel and optionally override fields via the console handler in the sample client.

Enable elicitation in your own client

The client advertises the elicitation capability only after you register a handler. Call SetElicitationHandler (or the builder helper) before Initialize:

var client = new McpClientBuilder()
    .UseSseTransport(serverUrl)
    .WithElicitationHandler(async (context, ct) =>
    {
        // Render UI, validate against context.RequestedSchema, then respond
        return ElicitationClientResponse.Decline();
    })
    .Build();

await client.Initialize();

Handlers can accept, decline, or cancel and receive strongly typed schema details via ElicitationRequestContext. The SimpleClient console demo in Mcp.Net.Examples.SimpleClient shows a full end-to-end implementation.

Create your first MCP server in 2 minutes

using Mcp.Net.Core.Attributes;
using Mcp.Net.Server;
using Mcp.Net.Server.ConnectionManagers;
using Mcp.Net.Server.Extensions;
using Microsoft.Extensions.Logging;

// 1. Create a simple stdio server
var server = new McpServer(
    new ServerInfo { Name = "QuickStart Server", Version = "1.0" },
    new InMemoryConnectionManager(new LoggerFactory())
);

// 2. Define tools using simple attributes a

... [View full README on GitHub](https://github.com/SamFold/Mcp.Net#readme)