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.

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. printEnv

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

5. 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

6. getTinyImage

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

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"]
     }
     

8. getResourceReference

   • Returns a resource reference that can be used by MCP clients
   • Inputs:
     • resourceId (number, 1-100): ID of the resource to reference
   • Returns: A resource reference with:
     • Text introduction
     • Embedded resource with type: "resource"
     • Text instruction for using the resource URI

9. startElicitation

   • Initiates an elicitation (interaction) within the MCP client.
   • Inputs:
     • color (string): Favorite color
     • number (number, 1-100): Favorite number
     • pets (enum): Favorite pet
   • Returns: Confirmation of the elicitation demo with selection summary.

10. structuredContent

• Demonstrates a tool returning structured content using the example in the specification
• Provides an output schema to allow testing of client SHOULD advisory to validate the result using the schema
• Inputs:
  • location (string): A location or ZIP code, mock data is returned regardless of value
• Returns: a response with
  • structuredContent field conformant to the output schema
  • A backward compatible Text Content field, a SHOULD advisory in the specification

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

3. resource_prompt

   • Demonstrates embedding resource references in prompts
   • Required arguments:
     • resourceId (number): ID of the resource to embed (1-100)
   • Returns: Multi-turn conversation with an embedded resource reference
   • Shows how to include resources directly in prompt messages

Logging

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

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

Usage with Claude Desktop (uses stdio Transport)

Add to your claude_desktop_config.json:

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

Usage with VS Code

For quick installation, use of of the one-click install buttons below...

For manual installation, you can configure the MCP server using one of these methods:

Method 1: User Configuration (Recommended) Add the configuration to your user-level MCP configuration file. Open the Command Palette (Ctrl + Shift + P) and run MCP: Open User Configuration. This will open your user mcp.json file where you can add the server configuration.

Method 2: Workspace Configuration Alternatively, you can add the configuration to a file called .vscode/mcp.json in your workspace. This will allow you to share the configuration with others.

For more details about MCP configuration in VS Code, see the official VS Code MCP documentation.

NPX

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

Running from source with HTTP+SSE Transport (deprecated as of 2025-03-26)

cd src/everything
npm install
npm run start:sse

Run from source with Streamable HTTP Transport

cd src/everything
npm install
npm run start:streamableHttp

Running as an installed package

Install

npm install -g @modelcontextprotocol/server-everything@latest

Run the default (stdio) server

npx @modelcontextprotocol/server-everything

Or specify stdio explicitly

npx @modelcontextprotocol/server-everything stdio

Run the SSE server

npx @modelcontextprotocol/server-everything sse

Run the streamable HTTP server

npx @modelcontextprotocol/server-everything streamableHttp