Sandboxer: hosted MCP gives agents a root-access cloud Ubuntu microVM
Sandboxer offers a hosted MCP endpoint so ChatGPT, Claude and Cursor agents can spin up a root-access Ubuntu 24.04 microVM, run detached long jobs and publish ports.
THIS IS A PURE F*CKING GOLDMINE you can now connect Claude Opus 5.5, GPT-Terra 6.1, or Sonnet 5.5 directly into an isolated cloud Ubuntu microVM over hosted MCP Sandboxer gives your agent full root access and its own kernel, so you can close your laptop while long tests run: how the architecture works: 1. Dedicated Cloud Kernel • runs in a Cloud Hypervisor microVM off your machine • full Ubuntu 24.04 with systemd as PID 1 and root access • Docker daemon pre-loaded and /dev/kvm enabled for nested jobs 2. Hosted MCP (Zero Install) • connect to sandboxer .com/mcp via Streamable HTTP • 18 sandbox tools ready instantly in Cursor, Claude, Codex, or ChatGPT • headless runs authenticate with an API key 3. The Autonomous Tool Loop • create_sandbox spins up the machine in 38ms • detached exec returns a processId so long builds never time out • command_status streams logs in real time • host_port exposes any internal port to a public HTTPS URL • stop_sandbox snapshots RAM to NVMe and stops billing immediately 4. Close Your Laptop Safe • run handoff_session in sbx mcp • checkpoints your repo on a temp branch and moves the session to the cloud • your .env stays on your local disk with zero cloud leaks the numbers: → $0.00/hr while paused (memory preserved in snapshot) → $0.036/hr only while actively running → versioned snapshots ensure two agents never overwrite state the prompt to paste into your agent once you add the MCP server: "Add sandboxer .com/mcp. Create a sandbox, clone this repo into it, run the tests detached, and publish the port. When the work is done, stop it so the memory stays and the bill stops. Show me the tool calls before you delete anything" try it here: ↳ http://sandboxer.com
This post quotes another post: x.com/jonoringer/status/2111826193578070439