Setup Review Sandbox

What it does

When your agent uses it

• The user says set up the review sandbox
• Install the sandbox prereqs
• Build the sandbox image
• A reproduce-issue preflight reports something MISSING

Example prompts

• “set up the review sandbox”
• “install the sandbox prereqs”
• “build the sandbox image”
• “/setup-review-sandbox”

Requirements

• Docker
• Pre-approved tools (allowed-tools): Read, Grep, Glob, Bash(uname *), Bash(docker info *), Bash(docker run *), Bash(docker build *), Bash(docker image inspect *), Bash(docker images *), Bash(command -v *), Bash(lsmod *), Bash(bash tools/review-sandbox/*), Bash(tools/review-sandbox/sandbox *)

Workflow steps

6 steps, taken from the step headings in SKILL.md.

1. 1Docker
2. 2Isolation runtime
3. 3Container networking (catches the veth class of breakage)
4. 4The toolchain image (nx-review-sandbox)
5. 5Verify (smoke test)
6. 6Reclaiming the disk

What it can do on your machine

Read from SKILL.md and the folder at commit 200edc8. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Read
  • Grep
  • Glob
  • Bash(uname *)
  • Bash(docker info *)
  • Bash(docker run *)
  • Bash(docker build *)
  • Bash(docker image inspect *)
  • Bash(docker images *)
  • Bash(command -v *)

  …and 3 more on the same allowed-tools line.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • docker
  • apt-get
  • curl
  • bash
  • mise
  • node
  • java
  • dotnet
  • brew

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Hosts in commands or code, which the agent is likely to contact:

  • gvisor.dev
  • storage.googleapis.com

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Setup Review Sandbox loads about 1.8k tokens when it runs. Until then it costs about 131 tokens; SKILL.md has 708 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~131

When it runs · the whole SKILL.md, loaded when a task matches

~1.8k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

• NoteRuns commands with sudoSKILL.md:19

  G, Linux:** install Docker Engine, then `sudo systemctl enable --now docker` and add yourself to the `docker` group (`su

• NoteRuns commands with sudoSKILL.md:33

  sudo apt-get update && sudo apt-get install -y apt-transport-https ca-certificates curl gnupg

• NoteRuns commands with sudoSKILL.md:34

  l -fsSL https://gvisor.dev/archive.key | sudo gpg --dearmor -o /usr/share/keyrings/gvisor-archive-keyring.gpg

• NoteRuns commands with sudoSKILL.md:35

  apis.com/gvisor/releases release main" | sudo tee /etc/apt/sources.list.d/gvisor.list

• NoteRuns commands with sudoSKILL.md:36

  sudo apt-get update && sudo apt-get install -y runsc

• NoteRuns commands with sudoSKILL.md:37

  sudo runsc install          # registers runsc as a Docker runtime

• NoteRuns commands with sudoSKILL.md:38

  sudo systemctl restart docker

• NoteRuns commands with sudoSKILL.md:61

  sudo modprobe veth

• NoteRuns commands with sudoSKILL.md:64

  it auto-loads. Persist it: `echo veth | sudo tee /etc/modules-load.d/veth.conf`.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from nrwl/nx at commit 200edc8, republished under its MIT licence (© nrwl). 708 words, ~1,768 tokens.

name

setup-review-sandbox

description

One-time setup of the sandbox prerequisites used by the reproduce-issue skill and the reproduce-verifier agent — Docker, the isolation runtime (gVisor on Linux / Colima on macOS), healthy container networking, and the nx-review-sandbox toolchain image (built from the repo's mise.toml). Idempotent; re-run any time to verify or repair. Use when the user says "set up the review sandbox", "install the sandbox prereqs", "build the sandbox image", or a reproduce-issue preflight reports something MISSING.

allowed-tools

Read, Grep, Glob, Bash(uname *), Bash(docker info *), Bash(docker run *), Bash(docker build *), Bash(docker image inspect *), Bash(docker images *), Bash(command -v *), Bash(lsmod *), Bash(bash tools/review-sandbox/*), Bash(tools/review-sandbox/sandbox *)

docker info >/dev/null 2>&1 && echo "docker OK" || echo "docker MISSING"

docker info --format '{{range $k,$v := .Runtimes}}{{$k}} {{end}}' | grep -q runsc && echo "runsc OK" || echo "runsc MISSING"

sudo apt-get update && sudo apt-get install -y apt-transport-https ca-certificates curl gnupg
curl -fsSL https://gvisor.dev/archive.key | sudo gpg --dearmor -o /usr/share/keyrings/gvisor-archive-keyring.gpg
echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/gvisor-archive-keyring.gpg] https://storage.googleapis.com/gvisor/releases release main" | sudo tee /etc/apt/sources.list.d/gvisor.list
sudo apt-get update && sudo apt-get install -y runsc
sudo runsc install          # registers runsc as a Docker runtime
sudo systemctl restart docker

docker info >/dev/null 2>&1 && echo "docker VM OK" || echo "start it: colima start"

docker run --rm --network none alpine true && echo "sandbox OK"
docker run --rm alpine true && echo "networking OK" || echo "networking BROKEN"

sudo modprobe veth

bash tools/review-sandbox/build-image.sh

# RUNTIME="--runtime=runsc"  on Linux, ""  on macOS
docker run --rm $RUNTIME nx-review-sandbox:latest bash -c '
  cd /work    # mise resolves versions from the mise.toml here; do NOT use bash -l (a login shell resets PATH, dropping the mise dirs)
  echo "kernel: $(uname -r)"       # Linux+gVisor: 4.19.0-gvisor ; macOS: the VM kernel
  mise ls | head
  node --version; java --version 2>&1 | head -1; dotnet --version
'

tools/review-sandbox/sandbox prune --store   # pnpm store prune + git gc in the shared repo
tools/review-sandbox/sandbox prune --host    # destroy the shared host; next start rebuilds it cold

© nrwl, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in .claude/skills/setup-review-sandbox of nrwl/nx.

Open the folder on GitHubat commit 200edc8