Calculator MCP Remote Server

You can use this SSE-based calculator as an MCP server to perform real-time, stateful calculations with an AI assistant. It streams updates via Server-Sent Events, keeps session history, and lets you manage ongoing calculations across a single session or multiple sessions for different users or tasks.

How to use

Connect your MCP client to the remote calculator stream to establish a real-time session. Create or attach to a session, then send calculation requests to perform basic arithmetic operations. You can continue calculating within the same session, view the evolving result, and review the history of all operations for that session.

How to install

Prerequisites: Node.js v14 or higher and npm v6 or higher.

Follow these steps to get the server running in your environment.

1. Ensure you have Node.js and npm installed.

2. Place the server code on your machine (no clone command is shown here). Make sure the project files are present.

3. Install dependencies.

npm install

4. Start the server in development mode.

npm run start:dev

5. Open the calculator interface in your browser.

http://localhost:3000

Additional configuration and endpoints

This server exposes an API through Server-Sent Events for real-time streaming and HTTP endpoints for actions such as starting streams, performing calculations, retrieving history, and listing sessions.

MCP and deployment configuration

To integrate with an MCP client, include the following MCP server configuration. This setup uses a remote HTTP stream endpoint.

{
  "mcpServers": {
    "remote_calculator": {
      "url": "http://localhost:3000/calculator/stream",
      "disabled": false,
      "alwaysAllow": [],
      "timeout": 60
    }
  }
}

Available tools

stream

Establishes an SSE connection to create and maintain a live calculator session, streaming updates and events to the MCP client.

calculate

Performs a calculation operation on a specified session, supporting add, subtract, multiply, divide, and clear actions.

history

Retrieves the calculation history for a given session to review past results.

sessions

Lists all active calculator sessions and their current state for management and monitoring.

mcp_integration

Provides the MCP integration layer that enables AI assistants to connect to and interact with calculator sessions through the MCP protocol.