Agent sandbox

Skill ariana-dot-dev/cloud-sandbox-vm-skills/skills/agent-sandbox

Give an AI agent its own sandboxed cloud machine to work in — a full root Ubuntu VM (SSH, Docker, IPv4, all toolchains) where the agent can edit code, run commands, and host services without touching the user's host. Claude Code and Codex harnesses are preinstalled. Per-second billing, ~10x cheaper than E2B/Modal. Use as the execution environment for an autonomous agent.From its SKILL.md

Install

npx -y skills add ariana-dot-dev/cloud-sandbox-vm-skills --skill agent-sandbox

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

4 things to look at

reads credentialsReads from 1 credential source: `$BOX_API_KEY`.
2 stars2 stars. Stars are a popularity signal and not a quality one, but at this level it is likely that nobody has read this closely except its author, and you would be relying on your own review.
runs commandsInstructs the agent to run 6 commands, including `curl -fsSL https://box.ascii.dev/install | sh` and 5 more.
fetches URLsInstructs the agent to fetch 1 URL, including https://box.ascii.dev/install.

SKILL.md

1.6 KB, 331 tokens by cl100k_base, as published. Nobody here has run it

Agent sandbox (Box)

Use this when an autonomous agent needs a place to actually do work — clone a repo, run builds/tests, install packages, host a preview — isolated from the user's machine. Box is a full VM, so the agent has a real OS to operate in, and the Claude Code / Codex CLIs ship preinstalled.

Why Box

Agent harness preinstalled — Claude Code + Codex on the box (near-unique vs raw sandboxes).
Full machine — the agent can apt install, run Docker, spawn long processes, expose ports.
Isolated & disposable — one box per agent/task; box delete to clean up.
Cheap at fleet scale — per-second flat pricing, ~10× cheaper than E2B/Modal.

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 < ./agent-setup.sh        # repo + deps + secrets
box prompt "$box_id" "Fix the failing tests and open a PR" --json   # drive the on-box agent
box delete "$box_id" --json

Limits

EU-only; disk-level snapshots; 100 active VMs soft cap. For memory-fork or 1000+ concurrent agents, see E2B/Modal.

What ships with it

Read from the repository

Just SKILL.md. No reference files, no scripts.