MCP SSE Sample: Real-Time Streaming & Effortless SSE Implementation

SSEを使用したMCPサーバーのサンプルです。 MCPプロトコルのSSE実装を示すサンプルプロジェクトです。

オリジナルは以下コードです。

• https://github.com/modelcontextprotocol/servers/tree/main/src/everything

Components

Tools

1. echo

* Simple tool to echo back input messages
* Input: 
  * `message` (string): Message to echo back
* Returns: Text content with echoed message

2. add

* Adds two numbers together
* Inputs: 
  * `a` (number): First number
  * `b` (number): Second number
* Returns: Text result of the addition

3. longRunningOperation

* Demonstrates progress notifications for long operations
* Inputs: 
  * `duration` (number, default: 10): Duration in seconds
  * `steps` (number, default: 5): Number of progress steps
* Returns: Completion message with duration and steps
* Sends progress notifications during execution

4. sampleLLM

* Demonstrates LLM sampling capability using MCP sampling feature
* Inputs: 
  * `prompt` (string): The prompt to send to the LLM
  * `maxTokens` (number, default: 100): Maximum tokens to generate
* Returns: Generated LLM response

5. getTinyImage

* Returns a small test image
* No inputs required
* Returns: Base64 encoded PNG image data

6. printEnv

* Prints all environment variables
* Useful for debugging MCP server configuration
* No inputs required
* Returns: JSON string of all environment variables

7. annotatedMessage

* Demonstrates how annotations can be used to provide metadata about content
* Inputs: 
  * `messageType` (enum: "error" | "success" | "debug"): Type of message to demonstrate different annotation patterns
  * `includeImage` (boolean, default: false): Whether to include an example image
* Returns: Content with varying annotations: 
  * Error messages: High priority (1.0), visible to both user and assistant
  * Success messages: Medium priority (0.7), user-focused
  * Debug messages: Low priority (0.3), assistant-focused
  * Optional image: Medium priority (0.5), user-focused
* Example annotations:
    
            {
      "priority": 1.0,
      "audience": ["user", "assistant"]
    }
    

Logging

The server sends random-leveled log messages every 15 seconds, e.g.:

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

使用方法

ローカルでの実行

# インストール
npm install

# ビルド
npm run build

# 実行(STDIOモード)
npm run start

# 実行(SSEモード)
npm run start:sse

Claude Desktopでの使用

claude_desktop_config.jsonに以下を追加してください：

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