Everything MCP Server

This MCP server attempts to exercise all the features of the MCP protocol. It is not intended to be a useful server, but rather a test server for builders of MCP clients. It implements prompts, tools, resources, sampling, and more to showcase MCP capabilities.

This server is a fork of modelcontextprotocol/servers with extended functionality for testing MCP clients.

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:
     • messages (array): Array of messages to send to the LLM, each containing:
       • role (enum: "user" | "assistant"): The role of the message sender
       • content (object): Either text or image content:
         • Text content:
           • type: "text"
           • text (string): The text content
           • annotations (optional): Audience and priority metadata
         • Image content:
           • type: "image"
           • data (string): Base64-encoded image data
           • mimeType (string): Image MIME type
           • annotations (optional): Audience and priority metadata
     • maxTokens (number): Maximum tokens to generate
     • modelPreferences (object, optional):
       • hints (array, optional): Model name hints in order of preference
       • costPriority (number, 0-1, optional): Priority for minimizing costs
       • speedPriority (number, 0-1, optional): Priority for minimizing latency
       • intelligencePriority (number, 0-1, optional): Priority for model capabilities
     • systemPrompt (string, optional): Optional system prompt override
     • includeContext (enum: "none" | "thisServer" | "allServers", optional): Whether to include MCP server context
     • temperature (number, optional): Controls randomness in the output
     • stopSequences (array of strings, optional): List of sequences that will stop generation
     • metadata (record, optional): Optional provider-specific metadata
   • Returns:
     • Model name used for generation
     • Generated content (text or image)
     • Optional stop reason ("endTurn", "stopSequence", "maxTokens", or other)

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"]
     }

Resources

The server provides 100 test resources in two formats:

• Even numbered resources:

  • Plaintext format
  • URI pattern: test://static/resource/{even_number}
  • Content: Simple text description

• Odd numbered resources:

  • Binary blob format
  • URI pattern: test://static/resource/{odd_number}
  • Content: Base64 encoded binary data

Resource features:

• Supports pagination (10 items per page)
• Allows subscribing to resource updates
• Demonstrates resource templates
• Auto-updates subscribed resources every 5 seconds

Prompts

1. simple_prompt

   • Basic prompt without arguments
   • Returns: Single message exchange

2. complex_prompt

   • Advanced prompt demonstrating argument handling
   • Required arguments:
     • temperature (number): Temperature setting
   • Optional arguments:
     • style (string): Output style preference
   • Returns: Multi-turn conversation with images

Usage with Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "everything": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-everything"
      ]
    }
  }
}