| Component | Build Status | NuGet Package |
|---|---|---|
| nanoFramework.WebServer |  |
|
| nanoFramework.WebServer.FileSystem |  |
|
| nanoFramework.WebServer.Mcp |  |
This library provides a lightweight, multi-threaded HTTP/HTTPS WebServer for .NET nanoFramework with comprehensive Model Context Protocol (MCP) support for AI agent integration.
- Multi-threaded request handling
- Static file serving with FileSystem support
- RESTful API support with parameter handling
- Route-based controllers with attribute decoration
- Authentication support (Basic, API Key)
- HTTPS/SSL support with certificates
- Model Context Protocol (MCP) for AI agent integration
- Automatic tool discovery and JSON-RPC 2.0 compliance
Using the Web Server is very straight forward and supports event based calls.
'''csharp // You need to be connected to a wifi or ethernet connection with a proper IP Address
using (WebServer server = new WebServer(80, HttpProtocol.Http)) { server.CommandReceived += ServerCommandReceived; server.Start(); Thread.Sleep(Timeout.Infinite); }
private static void ServerCommandReceived(object source, WebServerEventArgs e) { if (e.Context.Request.RawUrl.ToLower() == "/hello") { WebServer.OutPutStream(e.Context.Response, "Hello from nanoFramework!"); } else { WebServer.OutputHttpCode(e.Context.Response, HttpStatusCode.NotFound); } } '''
Controllers are supported including with parametarized routes like 'api/led/{id}/dosomething/{order}'.
'''csharp using (WebServer server = new WebServer(80, HttpProtocol.Http, new Type[] { typeof(MyController) })) { server.Start(); Thread.Sleep(Timeout.Infinite); }
public class MyController { [Route("api/hello")] [Method("GET")] public void Hello(WebServerEventArgs e) { WebServer.OutPutStream(e.Context.Response, "Hello from Controller!"); }
[Route("api/led/{id}")]
[Method("GET")]
public void LedState(WebServerEventArgs e)
{
string ledId = e.GetRouteParameter("id");
WebServer.OutPutStream(e.Context.Response, $"You selected Led {ledId}!");
}
} '''
Enable AI agents to interact with your embedded devices through standardized tools and JSON-RPC 2.0 protocol.
'''csharp public class IoTTools { [McpServerTool("read_sensor", "Reads temperature from sensor")] public static string ReadTemperature() { // Your sensor reading code return "23.5°C"; }
[McpServerTool("control_led", "Controls device LED", "Uutput the statusof the LED")]
public static string ControlLed(LedCommand command)
{
// Your LED control code
return $"LED set to {command.State}";
}
}
public class LedCommand { [Description("LED state: on, off, or blink")] public string State { get; set; } } '''
You can define reusable, high-level prompts for AI agents using the McpServerPrompt attribute. Prompts encapsulate multi-step instructions or workflows that can be invoked by agents.
Here's a simple example:
using nanoFramework.WebServer.Mcp;
public class McpPrompts
{
[McpServerPrompt("echo_sanity_check", "Echo test prompt")]
public static PromptMessage[] EchoSanityCheck()
{
return new PromptMessage[]
{
new PromptMessage("Call Echo with the string 'Hello MCP world!' and return the response.")
};
}
}Prompts can be discovered and invoked by AI agents in the same way as tools. You can also define prompts with parameters using the McpPromptParameter attribute.
'''csharp public static void Main() { // Connect to WiFi first var connected = WifiNetworkHelper.ConnectDhcp(Ssid, Password, requiresDateTime: true);
// Discover and register MCP tools
McpToolRegistry.DiscoverTools(new Type[] { typeof(IoTTools) });
// Discover and register MCP prompts
McpPromptRegistry.DiscoverPrompts(new Type[] { typeof(McpPrompts) });
// Start WebServer with MCP support
using (var server = new WebServer(80, HttpProtocol.Http, new Type[] { typeof(McpServerController) }))
{
// Optional customization
McpServerController.ServerName = "MyIoTDevice";
McpServerController.Instructions = "IoT device with sensor and LED control capabilities.";
server.Start();
Thread.Sleep(Timeout.Infinite);
}
} '''
Once running, AI agents can discover and invoke your tools:
'''json // Tool discovery POST /mcp { "jsonrpc": "2.0", "method": "tools/list", "id": 1 }
// Tool invocation POST /mcp { "jsonrpc": "2.0", "method": "tools/call", "params": { "name": "control_led", "arguments": {"State": "on"} }, "id": 2 } '''
| Topic | Description |
|---|---|
| Controllers and Routing | Learn about route attributes, method decorations, and URL parameters |
| Authentication | Configure Basic Auth, API Key, and custom authentication |
| HTTPS and Certificates | Set up SSL/TLS encryption with certificates |
| File System Support | Serve static files from storage devices |
| Model Context Protocol (MCP) | Complete MCP guide for AI agent integration |
| REST API Development | Build RESTful APIs with request/response handling |
| Event-Driven Programming | Handle requests through events and status monitoring |
| Examples and Samples | Working examples and code samples |
- No compression support in request/response streams
- MCP implementation supports server features only (no notifications or SSE)
- No or single parameter limitation for MCP tools (use complex objects for multiple parameters)
- Prompt parameters, when declared, are always mandatory.
Install 'nanoFramework.WebServer' for the Web Server without File System support. Install 'nanoFramework.WebServer.FileSystem' for file serving, so with devices supporting File System. Install 'nanoFramework.WebServer.Mcp' for MCP support. It does contains the full 'nanoFramework.WebServer' but does not include native file serving. You can add this feature fairly easilly by reusing the code function serving it.
For documentation, feedback, issues and contributions, please refer to the Home repo.
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The list of contributors to this project can be found at CONTRIBUTORS.
Licensed under the MIT license.
This project has adopted the code of conduct defined by the Contributor Covenant to clarify expected behaviour in our community. For more information see the .NET Foundation Code of Conduct.
This project is supported by the .NET Foundation.