@modelcontextprotocol/server-everything

Markdown Content: 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, add the following JSON block to your User Settings (JSON) file in VS Code. You can do this by pressing Ctrl + Shift + P and typing Preferences: Open User Settings (JSON).

Optionally, you can add it to a file called .vscode/mcp.json in your workspace. This will allow you to share the configuration with others.

Note that the mcp key is not needed in the .vscode/mcp.json file.

NPX

{ "mcp": { "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