MCP Web Worker Demo

Name: MCP Web Worker Demo
Author: weolopez

@weolopez

Repository

About MCP Web Worker Demo

mcp demo, client and server as web workers from a web UI

#mcp #web-worker #demo

Basic information

Config

Add this server to your MCP-compatible client using the configuration below.

{
  "mcpServers": {
    "mcp-worker": {
      "command": "npx",
      "args": [
        "http-server",
        "-p",
        "3000"
      ]
    }
  }
}

Tools

No tools detected

We auto-extract tools from the README. The maintainer can list them under a ## Tools heading to populate this section.

Overview

What is MCP Web Worker Demo?

MCP Web Worker Demo is a browser-based demonstration of a Model Context Protocol (MCP) client implemented using a Shared Web Worker architecture. It shows how to run MCP in a browser with a decoupled, pure JavaScript design requiring no build step.

How to use MCP Web Worker Demo?

Install the TypeScript SDK, build it with npm run build, then start a web server from the webworker-demo directory using ./start.sh or npx http-server -p 3000. Open http://localhost:3000/webworker-demo/ in Chrome or Edge, click “Connect to MCP”, and explore the Tools, Resources, and Prompts tabs.

Key features of MCP Web Worker Demo

Client runs in a Shared Web Worker background thread.
No external dependencies or build step required.
Single worker instance serves multiple tabs or windows.
Mock server with tools, resources, and prompts for testing.
Interactive demo UI showing connection state and server info.
Built-in diagnostics and detailed logging for troubleshooting.

Use cases of MCP Web Worker Demo

Demonstrating how to integrate MCP into a browser environment.
Testing MCP features like tool calling and resource reading.
Evaluating the performance benefits of offloading MCP to a worker.
Prototyping multi-tab applications that share a single MCP connection.

FAQ from MCP Web Worker Demo

What browsers are required to run MCP Web Worker Demo?

Shared Web Worker support is strictly required. Chrome, Edge (Chromium-based), Opera, and Android Chrome work. Firefox has limited support (disabled by default), and Safari/iOS Safari are not supported. No fallback is provided.

Does MCP Web Worker Demo need any external libraries or build tools?

No. The entire implementation uses pure JavaScript with ES modules and async/await. There are no external dependencies, and no build step is needed—just a local HTTP server.

Where does MCP Web Worker Demo store data?

All MCP client processing and mock server state run inside the Shared Web Worker context in the browser. No server‑side storage or external databases are used.

Why does MCP Web Worker Demo require a web server instead of opening the files directly?

Shared Workers cannot be loaded from the file:// protocol. The demo must be served over HTTP (e.g., http://localhost:3000) to function correctly.

Does MCP Web Worker Demo support authentication or secure transport?

The demo implements a self‑contained mock server with no authentication or transport security. It is intended only for local testing and demonstration.