language-server-mcp MCP Server

A Model Context Protocol (MCP) server providing language support for code editing.

This is a TypeScript-based MCP server designed to enhance code editing experiences by providing features such as hover information, code completion, and diagnostics. It demonstrates core MCP concepts by providing:

Language-specific tools for code analysis and manipulation
Integration with the Model Context Protocol for seamless communication

Features

Language Support

Provides hover information for symbols in code
Offers code completion suggestions
Reports diagnostic information (errors, warnings)
Only tested with typescript, theoretically should support Python. Would love to add additional language servers or be more agnostic if possible.

MCP Integration

Implements the MCP protocol for communication with clients
Exposes language features as MCP tools

Tools

get_hover: Get hover information for a position in a document
- Takes languageId, filePath, content, line, and character as required parameters
get_completions: Get completion suggestions for a position in a document
- Takes languageId, filePath, content, line, and character as required parameters
get_diagnostics: Get diagnostic information for a document
- Takes languageId, filePath, and content as required parameters

Development

Install dependencies:

npm install

Build the server:

npm run build

For development with auto-rebuild:

npm run watch

Installation

To use with Claude Desktop, add the server config:

On MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json On Windows: %APPDATA%/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "language-server-mcp": {
      "command": "/path/to/language-server-mcp/build/index.js"
    }
  }
}

Debugging

Since MCP servers communicate over stdio, debugging can be challenging. We recommend using the MCP Inspector, which is available as a package script:

npm run inspector

The Inspector will provide a URL to access debugging tools in your browser.