modelcontextprotocol/server-everything

A comprehensive MCP server that exercises all features of the Model Context Protocol, serving as a robust reference implementation. It is designed primarily as a test server for builders of MCP clients, showcasing a wide range of protocol capabilities.

Features

Tools

• echo: Echoes back input messages.

  • Input: message (string)
  • Returns: Text content with echoed message.

• add: Adds two numbers together.

  • Inputs: a (number), b (number)
  • Returns: Text result of the addition.

• longRunningOperation: Demonstrates progress notifications for long operations.

  • Inputs: duration (number, default: 10), steps (number, default: 5)
  • Returns: Completion message with duration and steps, sends progress notifications during execution.

• sampleLLM: Demonstrates LLM sampling capability using MCP sampling feature.

  • Inputs: prompt (string), maxTokens (number, default: 100)
  • Returns: Generated LLM response.

• getTinyImage: Returns a small test image.

  • No inputs required.
  • Returns: Base64 encoded PNG image data.

• printEnv: Prints all environment variables for debugging.

  • No inputs required.
  • Returns: JSON string of all environment variables.

• annotatedMessage: Demonstrates annotated messages with metadata.

  • Inputs: messageType ("error" | "success" | "debug"), includeImage (boolean, default: false)
  • Returns: Content with varying annotations and optional image.

Resources

• Provides 100 test resources:
  • Even numbered: Plaintext format, URI: test://static/resource/{even_number}
  • Odd numbered: Binary blob format, URI: test://static/resource/{odd_number}
• Supports pagination (10 items per page)
• Allows subscribing to resource updates
• Demonstrates resource templates
• Auto-updates subscribed resources every 5 seconds

Prompts

• simple_prompt: Basic prompt, single message exchange.
• complex_prompt: Advanced prompt with required (temperature) and optional (style) arguments, supports multi-turn conversation with images.

Logging

• Sends random-leveled log messages every 15 seconds, e.g., info, warning, error levels.

Other

• Intended for testing, not for production use
• Can be integrated with Claude Desktop via configuration

Category

• Testing & Debugging Tools

Tags

• mcp, reference-implementation, testing, examples

Source

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

Pricing

No pricing information provided; appears to be open-source.