Connect Claude Desktop

Connect HELIX once and Claude Desktop can use the same discovery, validation, and publishing capabilities as the HELIX CLI, exposed as typed MCP tools.

Before you start

• Install Claude Desktop.
• Install Node.js 20 or newer; node -v should print v20 or higher.
• Create a HELIX account.

Add HELIX

In Claude Desktop, open Settings → Developer → Edit Config. Add the helix entry to the top-level mcpServers object and leave any existing servers intact:

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

On Windows, use cmd if Claude cannot launch npx directly:

{
  "mcpServers": {
    "helix": {
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@hypersoniclabs/helix-mcp@latest"]
    }
  }
}

Save the file, fully quit Claude Desktop, and reopen it. Open the connector picker beside the chat box and confirm HELIX tools appear.

Sign in

Ask Claude to check your HELIX login. If needed, it calls start_login and gives you a browser link. Complete sign-in yourself, then Claude calls check_login. The token is written locally to ~/.helix/credentials.json; it is not returned to Claude.

For an SSH-only or headless machine, use token login before starting the MCP server. Do not wait for a browser callback that cannot reach the remote host.

Verify the connection

Ask Claude:

Use HELIX to list the available world templates, then tell me which one you recommend. Do not publish anything.

A result from list_templates confirms the server loaded and can reach HELIX. If the tool is missing, check that the config is valid JSON, that node -v reports 20 or newer, and that you fully restarted the desktop app.

Claude in Chrome

Claude in Chrome is a separate browser-control connector. Install the Chrome extension, then enable it from Claude Desktop under Settings → Connectors → Claude in Chrome. It lets Claude test a world in the browser, but it does not replace the HELIX MCP server: enable both in the same desktop conversation to build with HELIX tools and verify the result in Chrome.

The Chrome side-panel chat does not load local claude_desktop_config.json servers. Start the task from Claude Desktop when it needs both HELIX and browser control.