MCP Sse Sample

🚀 MCP SSE Example

This is an example project of an MCP server implemented using SSE (Server-Sent Events), demonstrating the implementation method of SSE in the MCP protocol.

🚀 Quick Start

✨ Features

This project showcases several components and their functionalities:

Tools

1. echo

   • A simple tool for echoing input messages.
   • Input:
     • message (string): The message to be echoed.
   • Return: Text content containing the echoed message.

2. add

   • Adds two numbers.
   • Input:
     • a (number): The first number.
     • b (number): The second number.
   • Return: Text of the addition result.

3. longRunningOperation

   • Demonstrates progress notifications during a long operation.
   • Input:
     • duration (number, default: 10): The duration in seconds.
     • steps (number, default: 5): The number of progress steps.
   • Return: A completion message containing the duration and the number of steps.
   • Sends progress notifications during execution.

4. sampleLLM

   • Demonstrates the LLM sampling ability using the MCP sampling function.
   • Input:
     • prompt (string): The prompt sent to the LLM.
     • maxTokens (number, default: 100): The maximum number of generated tokens.
   • Return: The response generated by the LLM.

5. getTinyImage

   • Returns a small test image.
   • No input required.
   • Return: Base64-encoded PNG image data.

6. printEnv

   • Prints all environment variables.
   • Used for debugging the MCP server configuration.
   • No input required.
   • Return: A JSON string of all environment variables.

7. annotatedMessage

   • Demonstrates how to use annotations to provide metadata for content.
   • Input:
     • messageType (enum: "error" | "success" | "debug"): Different message types to be displayed.
     • includeImage (boolean, default: false): Whether to include a sample image.
   • Return: Content with different annotations:
     • Error message: High priority (1.0), visible to both the user and the assistant.
     • Success message: Medium priority (0.7), for the user.
     • Debug message: Low priority (0.3), for the assistant.
     • Optional image: Medium priority (0.5), for the user.
   • Example annotation:

{
    "priority": 1.0,
    "audience": ["user", "assistant"]
}

Logs

The server sends random-level log messages every 15 seconds, for example:

{
    "method": "notifications/message",
    "params": {
        "level": "info",
        "data": "Info-level message"
    }
}

📦 Installation

Local Run

# Install
npm install

# Build
npm run build

# Run (STDIO mode)
npm run start

# Run (SSE mode)
npm run start:sse

Usage in Claude Desktop

Add the following content to the claude_desktop_config.json file:

{
    "mcpServers": {
        "sse-sample": {
            "command": "npx",
            "args": [
                "-y",
                "mcp_sse_sample"
            ]
        }
    }
}