rbxdev-ls

rbxdev-ls is a Luau language server and VS Code extension for Roblox development.
It gives you fast editor tooling, strict type checking, and optional live-game tooling through an executor bridge.

Install

• VS Code Marketplace: https://marketplace.visualstudio.com/items?itemName=rbxdev.rbxdev-ls
• Open VSX: https://open-vsx.org/extension/rbxdev/rbxdev-ls

What It Includes

Language Server Features

• Roblox API completions and hover docs
• Luau type checking (--!strict, --!nonstrict, --!nocheck)
• Go to definition, find references, rename, document symbols
• Signature help, inlay hints, semantic tokens
• Auto-import suggestions from workspace modules
• Formatting support

Live Roblox Features (Bridge Required)

• Game Tree explorer in the side bar
• Properties panel for the selected instance
• Execute current file or selection in-game
• Bundle and execute multi-file code
• Remote Spy utilities and quick-copy commands
• Actions like teleport, create/clone/delete/reparent, save instance/game

MCP / AI Integration

• Built-in language model tools exposed by the extension
• Standalone @oneshot101/rbxdev-mcp package for MCP-compatible clients
• Works with the same bridge connection as the extension

Default Shortcuts

• Ctrl+Shift+E: execute current file
• Ctrl+Shift+Alt+E: execute current selection
• Ctrl+Alt+E: bundle and execute
• Ctrl+Shift+R: copy last Remote Spy call
• Ctrl+Shift+Alt+R: insert last Remote Spy call
• Ctrl+Alt+C: quick copy last Remote Spy call

Quick Start

1. Install the extension from VS Code Marketplace or Open VSX.
2. Open a folder with .luau or .lua files.
3. Start writing Luau with type checking and completions enabled.

Example:

--!strict

local Players = game:GetService("Players")
local localPlayer = Players.LocalPlayer
local character = localPlayer.Character or localPlayer.CharacterAdded:Wait()

Executor Bridge Setup

To enable live game features, run this in your executor auto-execute:

loadstring(game:HttpGetAsync('https://raw.githubusercontent.com/0neShot101/rbxdev-ls/main/scripts/executor-bridge.lua'))()

Default bridge port: 21324
You can change it with the setting rbxdev-ls.executorBridge.port.

Optional custom bridge config:

loadstring(game:HttpGetAsync('https://raw.githubusercontent.com/0neShot101/rbxdev-ls/main/scripts/executor-bridge.lua'))({
    host = 'ws://127.0.0.1:21324';
    reconnectDelay = 5;
    firstConnectDepth = 999;
    updateTreeDepth = 2;
    expandedTreeDepth = 2;
})

MCP Setup (Standalone)

If you want MCP tools in external clients (Claude Code, Cursor, etc.), add:

{
  "mcpServers": {
    "rbxdev-roblox": {
      "command": "npx",
      "args": ["-y", "@oneshot101/rbxdev-mcp"]
    }
  }
}

Notes:

• Requires Node.js 18+
• Uses port 21324 by default
• If the VS Code extension is already running, MCP can connect through it as a proxy

Extension Settings

Common settings:

• rbxdev-ls.typeCheckMode: strict, nonstrict, or nocheck
• rbxdev-ls.enableSuncApi: enable/disable Sunc API definitions
• rbxdev-ls.executorBridge.port: WebSocket port for bridge connections
• rbxdev-ls.mcp.enabled: enable/disable built-in MCP server integration
• rbxdev-ls.bundler.path: custom luau-bundle path
• rbxdev-ls.debugLogs: verbose extension logging

Development

Prerequisites:

• Bun >= 1.0.0
• Node.js >= 18 (for MCP package workflows)

Install dependencies:

bun install
cd vscode && bun install

Common commands (repo root):

bun run build         # Build language server
bun run build:mcp     # Build MCP server entry
bun run build:all     # Build server + MCP + studio plugin assets
bun run test          # Run test suite
bun run type-check    # TypeScript checks
bun run lint:check    # ESLint (no fixes)
bun run format:check  # Prettier check
bun run fetch-api     # Update Roblox API data
bun run build:vsix    # Build VSIX package
bun run build:beta    # Build beta VSIX package
bun run build:studio  # Build Roblox Studio plugin artifacts

Package VS Code extension directly:

cd vscode
bun run package

Repository Layout

src/
  @core/         LSP server and connection setup
  @lsp/          Language server handlers
  @parser/       Luau lexer/parser/doc comments
  @typings/      Type system and checker
  @definitions/  Roblox, stdlib, and executor definitions
  @workspace/    Workspace and Rojo integration
  @executor/     Bridge protocol and runtime state
  @mcp/          MCP server implementation

vscode/          VS Code extension source and packaging
packages/rbxdev-mcp/  Standalone MCP npm package
scripts/         Build and maintenance scripts
studio-plugin/   Roblox Studio plugin source
tests/           Unit and integration tests

Contributing

Issues and pull requests are welcome.
If you add behavior, include or update tests in tests/.

License

MIT. See LICENSE.