Roblox Studio MCP

Let an AI agent drive Roblox Studio: read your place, edit scripts, build geometry, run playtests, take screenshots. 35 tools.

Install

Runs on Windows (x64, ARM) and macOS (Apple silicon, Intel). The server is a native binary that npm picks for your platform; npx needs Node 18 or newer.

1. The plugin

npx -y @el4cteo/rbx-studio-mcp --install-plugin

Or drop StudioMCP.rbxmx from Releases into your Studio plugins folder.

2. The server

claude mcp add rbx-studio -- npx -y @el4cteo/rbx-studio-mcp

codex mcp add rbx-studio -- npx -y @el4cteo/rbx-studio-mcp

{
  "mcpServers": {
    "rbx-studio": {
      "command": "npx",
      "args": ["-y", "@el4cteo/rbx-studio-mcp"]
    }
  }
}

{
  "mcp": {
    "rbx-studio": {
      "type": "local",
      "command": ["npx", "-y", "@el4cteo/rbx-studio-mcp"],
      "enabled": true
    }
  }
}

3. Open Studio and accept the 127.0.0.1 prompt. Check it works with studio_status.

Something wrong? Run npx -y @el4cteo/rbx-studio-mcp doctor. It says what is broken and how to fix it.

The port is 44755. Change it with --port and match it in the plugin.

Tools

Write tools take arrays: ten script edits is one call and one Ctrl+Z, and either all apply or none do.

device emulation stays on until device op="stop".

Why this one

• Fast: the bridge pushes calls instead of polling, 13.6 ms per call against 25.8 ms.
• Safe script edits: writes go through the script editor, so unsaved work survives.
• Stale edits are refused: line-range and whole-file edits need the rev from script_read.
• Property names are checked against the running engine, so Anchorred comes back as a suggestion, not a runtime error.

Debug a playtest

A playtest connects a second session, so pass its studioId. Use the edit session for changes that must last.

Readers can run in the player's own client with target="client" (add player="Name" with several players):

tree target="client" path="Players.Alice.PlayerGui" handles=true
find target="client" className="TextButton"
viewport op="pick" x=0.5 y=0.5 target="client"
debug op="watch" path=... target="client" properties=["Text"] seconds=5

• Handles (handles=true) replace paths. They survive renames and moves, and fail once the object is deleted or expired.
• viewport op="uisnap" snapshots a UI. Call it again with compareTo="<id>" to see what changed.
• debug op="collisions" reports what a part or model hit, hardest first.
• performance op="microprofile" ranks the engine scopes that filled your frames. Uses Roblox's LibMP (MIT).
• collision op="cast" sweeps rays, blocks, spheres or a real part.
• Clipped execute_luau results return a resultId. Page through it for 120 seconds without rerunning.

Work on files

sync mirrors your scripts into a folder, so an agent can edit code with its own file tools and use Studio to test.

sync op="pull"      # Studio -> ./studio
sync op="push"      # ./studio -> Studio
sync op="watch"     # both ways, live, until op="stop"

• Layout: Rojo-style (Main.server.luau, .client.luau, .luau), plus a sourcemap.json for luau-lsp.
• Renames: rename or move a file and the script moves with it.
• Conflicts: edited on both sides means neither is touched. Studio's version waits in .rbx-sync/conflicts/. Merge it and sync again, or pass prefer: "studio" or "disk".
• Deletes: deleting a file deletes the script (one Ctrl+Z). A script deleted in Studio sends its file to .rbx-sync/trash.
• UI as files: export writes an instance tree as a .build.json file, and build rebuilds it.

Open Cloud

Some calls reach past Studio to Roblox itself and need an API key. Everything else works without one.

Make a key at Creator Dashboard → Credentials, then in the Studio panel:

cloud key <paste>
cloud user <your user id>
cloud place <place id>

The key is stored at ~/.rbx-studio-mcp/credentials.json, never in the place file or the conversation. cloud shows what is set, cloud test re-checks it, cloud forget deletes it. ROBLOX_API_KEY and friends in the environment take priority.

Per-game permissions. Agents can only read a game's settings until you allow more. Type allow in the panel to see the list for the open game, allow <group> to turn one on, allow <group> off to turn it off. Groups: read, assets, data, edit (settings, publishing, restarts, live Luau), money (products and passes), players (bans).

The console panel

Every call is logged with how long it took. At the foot of the panel is a command line: click it to see every command, or type help.

Six themes with animated backgrounds: Nebula, Ember, Tide, Galaxy, Aurora and Monolith. Pick one from the dots in the header or with theme <name>; background off turns the animation off.

Run chat on and sentences you type go to a real coding agent. It uses any of 31 supported agents on your PATH, like Claude Code, Codex or Gemini; agent lists them and agent use <id> picks one. It runs separately from your terminal and is billed separately. Claude Code and Copilot are limited to the rbx-studio tools; the others use their own permission settings. The stop button cancels it.

Run playpanel on to also show the panel during playtests (off by default). playpanel left, right or bottom docks it there; playpanel float floats it at the panel's size.

Security

The server only listens on loopback. Requests need a header a browser cannot set cross-origin and a loopback Host, so a web page cannot reach it, even through DNS rebinding. Your experience's "Allow HTTP Requests" setting is untouched.

Development

The server is Rust (server/, toolchain pinned to 1.99.1); the plugin is Luau (plugin/).

cargo build --release --manifest-path server/Cargo.toml
node scripts/install-plugin.mjs   # build the plugin and copy it into Studio
cargo test --manifest-path server/Cargo.toml
node scripts/test-native.mjs      # black-box MCP and bridge tests

The plugin checks need luau, luau-compile and luau-analyze from the Luau releases on PATH or in tools/.

Live tests need Studio open with the plugin loaded, and they clean up after themselves: scripts/test-live.mjs, test-live-tools.mjs [--playtest], test-live-sync.mjs and test-live-sync-scale.mjs.

Shoutout

Thanks to GameDevTool for featuring this project in their roundup of free AI tools for Roblox Studio.

Licence

MIT.