CustomJS MCP Server

A remote Model Context Protocol server that gives AI agents web superpowers — host HTML pages on a public URL, generate PDFs, capture screenshots, scrape sites, and run sandboxed code — using your own CustomJS API key.

There's nothing to install or self-host — it's a hosted remote MCP server. Bring your CustomJS API key and connect.

Tools

Related MCP server: boxpdf-html

Get an API key

Create a free key at https://www.customjs.space/integration/native-api/api-key. Your key is sent per request as the x-customjs-api-key header and is never stored by the connector.

Connect

Claude Code — plugin (recommended)

/plugin marketplace add customjs/claude-plugin
/plugin install customjs@customjs-tools

You'll be prompted only for your API key. (See customjs/claude-plugin.)

Claude Code — without the plugin

claude mcp add --transport http \
  --header "x-customjs-api-key: <your-key>" \
  customjs https://mcp.customjs.space/customjs/mcp

Claude Desktop (JSON config via mcp-remote)

{
  "mcpServers": {
    "customjs": {
      "command": "npx",
      "args": [
        "-y", "mcp-remote",
        "https://mcp.customjs.space/customjs/mcp",
        "--header", "x-customjs-api-key:${CUSTOMJS_API_KEY}"
      ],
      "env": { "CUSTOMJS_API_KEY": "your-key" }
    }
  }
}

Other MCP clients (Cursor, VS Code, etc.)

Add a remote / HTTP MCP server pointing at https://mcp.customjs.space/customjs/mcp with the header x-customjs-api-key: <your-key>.

Hosting HTML pages

customjs_host_html_page publishes static HTML and returns a public https://lp.customjs.space/<shortId> URL. Hosting again with the same name updates the existing page (upsert by name).

Note: the public URL is served via CloudFront, so immediately after an update it may briefly show the previous content until the cache refreshes.

Official MCP Registry

This server is published to the official MCP Registry as space.customjs/customjs-mcp (DNS-verified on customjs.space) — see server.json. For how it's published and the full directory list, see PUBLISHING.md.

Links

• Website — https://www.customjs.space

• Get an API key — https://www.customjs.space/integration/native-api/api-key

• Claude Code plugin — https://github.com/customjs/claude-plugin

• MCP protocol — https://modelcontextprotocol.io

License

The contents of this repository (documentation and registry manifest) are released under the MIT License. The CustomJS service itself requires a valid API key and is governed by CustomJS's terms of service at https://www.customjs.space.