MCP

PlayerVox OverCrow has a server for AI assistants: @overcrow/mcp. Add it to Claude Code, Claude Desktop, Cursor, VS Code or Codex, and your assistant can create a widget, check it, test it, audit it, package it and prepare its submission. You need Node.js 22.18 or later, nothing else: the server installs the OverCrow tools it needs by itself.

claude mcp add overcrow -- npx -y @overcrow/mcp

Then ask: "Create a PlayerVox OverCrow widget that shows…".

Add the server

Open your widgets folder in the assistant, then add the server.

In one command

Claude Code, from that folder:

claude mcp add overcrow -- npx -y @overcrow/mcp

Codex:

codex mcp add overcrow -- npx -y @overcrow/mcp

VS Code: install in VS Code, or:

code --add-mcp '{"name":"overcrow","command":"npx","args":["-y","@overcrow/mcp"]}'

With a configuration file

Cursor: a .cursor/mcp.json file in the folder.

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

VS Code: a .vscode/mcp.json file in the folder.

{
  "servers": {
    "overcrow": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@overcrow/mcp"]
    }
  }
}

Claude Desktop starts its servers outside your folders: name your widgets folder with --root in claude_desktop_config.json (Settings, Developer, Edit Config), then restart Claude Desktop.

{
  "mcpServers": {
    "overcrow": {
      "command": "npx",
      "args": ["-y", "@overcrow/mcp", "--root", "C:\\Users\\you\\Documents\\widgets"]
    }
  }
}

What the server does

• The first time, it downloads the PlayerVox OverCrow creator tools of your computer (the command-line tool and the runtime that plays the tests, about 15 MB) from OverCrow's GitHub release. It checks every file against the digests written in the server, then keeps them in its own folder (~/.cache/overcrow-mcp, or %LOCALAPPDATA%\overcrow-mcp on Windows). Nothing goes on your PATH, and no administrator right is needed.
• Then your assistant works with its tools, in this order: create the widget from a template, install the SDK (it asks you first), check, test (it sees the images that differ), audit, package, prepare the submission.
• The widget ID is final. Your assistant asks you for it: your publisher handle in the PlayerVox OverCrow creator space and a name (nova.lol-timers), or a domain you can verify (gg.nova.lol-timers).
• The submission: the server checks everything the creator space asks for, then writes the ZIP of your widget's sources to dist/, without node_modules, dist, hidden files or keys, and lists what it left out. It also lists the texts to write: why the widget needs each permission, the release notes and the description in English and French. Your assistant drafts them with you.
• The audit scores the widget out of 100 for security and for lightness, with a fix and an example from a reference widget for each finding: unused permissions, network rules that are too broad, secrets, clipboard writes without a user action, fast timers, network polling, lists that never stop growing, large responses read in one turn, heavy images.
• The documentation of this site, in English and French, and the sources of the reference widgets come with the server: your assistant reads them without network access.

What it does not do

• It never sends, signs or publishes anything. You send the ZIP and the texts in the PlayerVox OverCrow creator space, at creators.playervox.com.
• It does not install your widget in PlayerVox OverCrow: trying it in a game is the development channel of the command-line tool.
• It sends nothing about you: no telemetry, no account.

Security

• Your folders only. The server works in the folder open in your assistant (or the ones given with --root). It refuses a system folder, your whole home folder, hidden folders, and links that lead outside.
• No command of its own choice. The server runs the PlayerVox OverCrow command-line tool and npm, nothing else, never through a shell.
• Checked downloads. It downloads only the pinned files from GitHub, and checks them before use. npm installs only @overcrow/sdk and TypeScript, with install scripts disabled, and their integrity is checked against the published packages.
• You confirm. Installing packages and replacing reference images need your agreement.
• Your files are data. What the tools return from your files is marked as data: a text inside a widget cannot give orders to your assistant through the server. Still read what your assistant changes, and approve its actions as you usually do.

Offline

Download overcrow-creator-tools-VERSION-PLATFORM.zip of your platform from PlayerVox OverCrow's GitHub release once, put it in your widgets folder, and ask your assistant to run setup with it (zipPath). Or start the server with --tools-zip and the path of the file. The file must be exactly the one the server pins.

Supported computers

Checking, testing and packaging need Windows x64 or Linux x86-64. On macOS and on ARM, the server still gives the documentation, the explanations and the audit.

If something goes wrong

• "not tied to a published OverCrow release": update the server with npx -y @overcrow/mcp@latest.
• Behind a proxy: set HTTPS_PROXY in the server's environment.
• "cannot work in /" (often Claude Desktop): add --root and your widgets folder.