Give Claude or Cursor a cloud sandbox, a database and a publish button over MCP

Mythex, an AI app builder based in Dubai, released a remote MCP server at mcp.mythex.ai/mcp that gives coding agents in Claude, Cursor and Codex a cloud sandbox, live preview, Postgres database, file storage, secrets and a public publish URL through a single OAuth connection with no API keys. The server exposes tools such as set_run_config, start_preview and get_preview, and every tool result returns a workspace_url so developers can watch the live preview in a browser while the agent works in the editor. The company says the same pattern applies to any MCP server that exposes a sandbox.

Coding agents in Claude, Cursor and Codex are good at writing code. They're weaker at everything around it: a machine to run the app on, a live preview, a database, file storage, secrets and a public URL at the end. Usually you wire that up yourself. This post shows how to hand all of that to the agent through one remote MCP server. I build Mythex, an AI app builder from Dubai, and this is how its MCP server works. The pattern applies to any MCP server that exposes a sandbox. Once connected, the client can: bash set run config , start preview , get preview Every tool result includes a workspace url , so you can watch the live preview in the browser while the agent works in your editor. https://mcp.mythex.ai/mcp Add the server with only the URL .cursor/mcp.json : { "mcpServers": { "mythex": { "url": "https://mcp.mythex.ai/mcp" } } } Toggle it on, click Connect when Cursor prompts, and approve in the browser. There are no API keys to paste: it's OAuth with refresh tokens. Create a new Mythex project called "booking-demo": a React + TypeScript app where clients book 30-minute slots. Store bookings in Postgres, start the preview, check it in the browser and send me a screenshot. When it works, publish it. The agent creates the project, writes the code in the sandbox, adds the database, starts the preview, checks it with a browser run, and publishes. You get back a preview URL, screenshots and a public URL. upgrade url instead of running. If you'd rather build in a chat UI, the same projects open in the Mythex web app. It also works in Arabic and 68 other languages.