lsp-mcp-rs

MCP server that bridges to any LSP. One binary, multiple language servers.

Build

cargo build --release

Binary: target/release/lsp-mcp-rs.exe

Configure

Create config.toml next to the binary:

[servers.lua]
command = "C:/path/to/lua-language-server.exe"
args = ["--stdio"]
extensions = [".lua"]

[servers.rust]
command = "rust-analyzer"
args = []
extensions = [".rs"]

[servers.python]
command = "pyright-langserver"
args = ["--stdio"]
extensions = [".py"]

Add to Claude Desktop config (claude_desktop_config.json):

{
  "mcpServers": {
    "lsp": {
      "command": "X:\\path\\to\\lsp-mcp-rs.exe",
      "args": []
    }
  }
}

Tools

Tool	Description
lsp_hover	Get docs/type at position
lsp_definition	Go to definition
lsp_references	Find all references
lsp_symbols	List symbols in file
lsp_diagnostics	Get errors/warnings
lsp_servers	List configured servers

All position arguments are 0-indexed.

How it works

1. MCP request comes in with a file path
2. File extension maps to configured LSP server
3. LSP spawns on first use, stays running
4. Request forwarded to LSP, response returned via MCP

License

MIT

Authors

DC, KALIC, Stryk9190