MCP Language Server is a bridge that connects MCP-enabled AI coding assistants to Language Server Protocol (LSP) implementations, giving LLMs access to semantic code intelligence tools. Key capabilities: - Go-to-definition navigation for understanding code structure - Find references across the codebase - Symbol renaming with safe refactoring - Real-time diagnostics and error detection - Support for multiple language servers including gopls (Go), rust-analyzer (Rust), and other LSP-compatible tools - Works with Claude Desktop, Cursor, and other MCP clients

MCP Language Server

[](https://github.com/isaacphi/mcp-language-server/actions/workflows/go.yml) [](https://goreportcard.com/report/github.com/isaacphi/mcp-language-server) [](https://pkg.go.dev/github.com/isaacphi/mcp-language-server) [](https://github.com/isaacphi/mcp-language-server/blob/main/go.mod)

This is an MCP server that runs and exposes a language server to LLMs. Not a language server for MCP, whatever that would be.

Demo

mcp-language-server helps MCP enabled clients navigate codebases more easily by giving them access semantic tools like get definition, references, rename, and diagnostics.

Setup

1. Install Go: Follow instructions at 2. Install or update this server: go install github.com/isaacphi/mcp-language-server@latest 3. Install a language server: _follow one of the guides below_ 4. Configure your MCP client: _follow one of the guides below_

Go (gopls) Install gopls: go install golang.org/x/tools/gopls@latest Configure your MCP client: This will be different but similar for each client. For Claude Desktop, add the following to ~/Library/Application\ Support/Claude/claude_desktop_config.json

{ "mcpServers": { "language-server": { "command": "mcp-language-server", "args": ["--workspace", "/Users/you/dev/yourproject/", "--lsp", "gopls"], "env": { "PATH": "/opt/homebrew/bin:/Users/you/go/bin", "GOPATH": "/users/you/go", "GOCACHE": "/users/you/Library/Caches/go-build", "GOMODCACHE": "/Users/you/go/pkg/mod" } } } }

Note: Not all clients will need these environment variables. For Claude Desktop you will need to update the environment variables above based on your machine and username:

PATH needs to contain the path to go and to gopls. Get this with echo $(which go):$(which gopls) GOPATH, GOCACHE, and GOMODCACHE may be different on your machine. These are the defaults.

Rust (rust-analyzer) Install rust-analyzer: rustup component add rust-analyzer Configure your MCP client: This will be different but similar for each client. For Claude Desktop, add the following to ~/Library/Application\ Support/Claude/claude_desktop_config.json

{ "mcpServers": { "language-server": { "command": "mcp-language-server", "args": [ "--workspace", "/Users/you/dev/yourproject/", "--lsp", "rust-analyzer" ] } } }

Python (pyright) Install pyright: npm install -g pyright Configure your MCP client: This will be different but similar for each client. For Claude Desktop, add the following to ~/Library/Application\ Support/Claude/claude_desktop_config.json

{ "mcpServers": { "language-server": { "command": "mcp-language-server", "args": [ "--workspace", "/Users/you/dev/yourproject/", "--lsp", "pyright-langserver", "--", "--stdio" ] } } }

Typescript (typescript-language-server) Install typescript-language-server: npm install -g typescript typescript-language-server Configure your MCP client: This will be different but similar for each client. For Claude Desktop, add the following to ~/Library/Application\ Support/Claude/claude_desktop_config.json

{ "mcpServers": { "language-server": { "command": "mcp-language-server", "args": [ "--workspace", "/Users/you/dev/yourproject/", "--lsp", "typescript-language-server", "--", "--stdio" ] } } }

C/C++ (clangd) Install clangd: Download prebuilt binaries from the official LLVM releases page or install via your sys