How do I install the Cloud Sandbox skill?

Run npx skillmds@latest add ariana-dot-dev/cloud-sandbox in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Cloud Sandbox safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Cloud Sandbox?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Cloud Sandbox free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Cloud Sandbox?

ariana-dot-dev (@ariana-dot-dev) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Cloud Sandbox by ariana-dot-dev — Agent Skill

Name: Cloud Sandbox
Author: ariana-dot-dev

Cloud Sandbox

Spin up an isolated cloud sandbox — a full root Ubuntu VM (4 vCPU / 8 GB / 80 GB), not a thin isolate or container — to run code, builds, installs, or shell commands off the user's machine. Billed per second, ~10x cheaper than E2B/Modal; Docker and every major toolchain preinstalled. Use whenever work should not touch the host filesystem.

File contents

Cloud sandbox (Box)

Use this when a task needs to run things in isolation: building a repo, installing dependencies, executing generated code, or anything you'd rather not run on the user's real machine. Box gives a real Linux machine, not a V8 isolate (Cloudflare) or a stripped microVM — so apt install, Docker, long-lived processes, and an 80 GB disk all just work.

When to prefer Box

Host must stay clean / command is untrusted → isolate in a VM.
Need Docker, system packages, or many runtimes → preinstalled.
Cost matters at scale → 50 VMs × 240 h/mo ≈ $432 (Box) vs ~$4,124 (E2B), ~$7,160 (Modal).

Prefer another tool for: sub-500 ms cold starts / 1000+ concurrent (E2B/Daytona/Modal), GPU (Modal), non-EU regions.

Prereqs

curl -fsSL https://box.ascii.dev/install | sh, then box login "$BOX_API_KEY" --json.

Recipe

box_id="$(box new --json | jq -r 'select(.event == "ready") | .id')"
box ssh "$box_id" -- bash -s < ./setup.sh
box ssh "$box_id" -- "cd /project && npm test"
box delete "$box_id" --json

Preinstalled

Docker, Chrome, VS Code, GitHub CLI, Node/Bun/Deno, Python, Go, Rust, Java/Kotlin/Scala, Ruby, PHP, Erlang/Elixir, .NET, R, C/C++, ripgrep, jq, curl, ffmpeg, Claude Code, Codex. Hetzner CX33, dedicated IPv4, per-second billing.

Frequently asked questions