Docker Skill

Installs and uses Docker reliably with official docs. Use when installing Docker (Desktop or Engine), building or running containers, writing Dockerfiles, using docker compose, or when the user asks about containers, images, or Docker CLI.

Docker — Install and Use Containers

Enables OpenClaw (and Cursor) to install Docker and use it reliably. Base all guidance on official Docker docs; when in doubt, fetch from canonical URLs below.

When to Apply

• User wants to install Docker (macOS, Linux, Windows)
• User asks about containers, images, Dockerfile, docker compose
• Building, running, or debugging Docker commands or workflows
• User asks for "latest Docker docs" or "how do I use Docker"

Canonical Documentation URLs

Purpose	URL
Get started / overview	https://docs.docker.com/get-started/overview/
Get Docker (install)	https://docs.docker.com/get-started/get-docker/
Develop with containers	https://docs.docker.com/get-started/introduction/develop-with-containers/
Guides	https://docs.docker.com/guides/
Manuals (install, config, use)	https://docs.docker.com/manuals/
Reference (CLI, Dockerfile, API)	https://docs.docker.com/reference/
Engine install (Linux)	https://docs.docker.com/engine/install/
Docker Desktop Mac	https://docs.docker.com/desktop/install/mac-install/
Docker CLI reference	https://docs.docker.com/reference/cli/docker/
Dockerfile reference	https://docs.docker.com/reference/dockerfile/

Rule: For install steps, CLI syntax, or Dockerfile instructions, fetch the relevant doc URL and use that content. Do not rely on training data for version-specific install or command details.

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Installation (Reliable Paths)

macOS

Recommended: Docker Desktop

1. Download from official docs: Install Docker Desktop on Mac.
   • Apple Silicon: https://desktop.docker.com/mac/main/arm64/Docker.dmg
   • Intel: https://desktop.docker.com/mac/main/amd64/Docker.dmg
2. Open Docker.dmg, drag Docker to Applications, then open Docker.app and accept terms.
3. CLI install (optional): After downloading the DMG:

   sudo hdiutil attach Docker.dmg
   sudo /Volumes/Docker/Docker.app/Contents/MacOS/install
   sudo hdiutil detach /Volumes/Docker
   

4. Verify: docker run hello-world

OpenClaw / automation: If docker is missing and the user is on macOS, suggest installing via Homebrew: brew install --cask docker, then starting Docker Desktop so the daemon is running.

Linux (Ubuntu example)

1. Prefer Docker Engine from apt (see Install Docker Engine on Ubuntu).
2. Remove conflicting packages first:

   sudo apt remove $(dpkg --get-selections docker.io docker-compose docker-compose-v2 docker-doc podman-docker containerd runc 2>/dev/null | cut -f1)
   

3. Add Docker’s apt repo, then:

   sudo apt update
   sudo apt install -y docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin
   sudo systemctl start docker
   sudo docker run hello-world
   

4. Optional (run without sudo): Linux postinstall — add user to docker group.

Convenience script (dev/test only): curl -fsSL https://get.docker.com -o get-docker.sh && sudo sh get-docker.sh. Not recommended for production.

Windows

Use Get Docker and follow Docker Desktop for Windows (WSL2 backend recommended).

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Core Workflow: Build and Run

1. Dockerfile in app directory (see reference.md or Dockerfile reference).
2. Build image: docker build -t <name> .
3. Run container: docker run -d -p HOST_PORT:CONTAINER_PORT <name> (e.g. -p 127.0.0.1:3000:3000).
4. List containers: docker ps (running), docker ps -a (all).
5. Stop/remove: docker stop <container>, docker rm <container>.

Example from official getting-started:

docker build -t getting-started .
docker run -d -p 127.0.0.1:3000:3000 getting-started
# Open http://localhost:3000

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Daemon Must Be Running

• Docker Desktop (Mac/Windows): Ensure Docker Desktop app is running; docker CLI talks to its daemon.
• Linux: sudo systemctl start docker (and enable if needed).
• If the user sees "Cannot connect to the Docker daemon", direct them to start Docker Desktop or the engine service and try again.

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Quick Reference

• Images: docker pull <image>, docker images, docker rmi <image>
• Containers: docker run, docker ps, docker stop, docker rm, docker logs <container>
• Compose: docker compose up -d, docker compose down — use compose.yaml in project root (see Compose file reference).
• Cleanup: docker system prune -a (removes unused images/containers/networks; use with care).

Additional Resources

• For detailed CLI and Dockerfile syntax, see reference.md.
• For full specs, fetch from the official reference and guides.