Docker Cli

---

name: docker-cli description: Helper for using the Docker CLI to build, run, stop, inspect, and manage containers and images. Use when the user wants to perform container-related tasks from the command line, such as building images, running services, cleaning up resources, or checking logs.

---

Docker CLI Helper

This skill explains how to use the Docker command line for common container workflows.

When to Use

Use this skill when:

The user wants to build or rebuild a Docker image.

The user wants to run a container (one-off or long-running).

The user wants to see which containers/images/volumes exist.

The user wants to stop or remove containers/images.

The user wants to see logs, exec into a container, or check resource usage.

Requirements

Docker is installed and running.

docker version or docker info works in the user’s shell.

If unsure, suggest the user run:

docker version

to confirm Docker is available.

Safety Guidelines

Prefer read-only or non-destructive commands first:

- docker ps, docker ps -a - docker images - docker logs - docker inspect

Be cautious with destructive commands:

- docker rm, docker rmi - docker system prune - docker volume rm

Only recommend destructive cleanups when the user explicitly wants to free resources and understands what will be removed.

Common Workflows

1. List and inspect containers

List running containers:

docker ps

List all containers (including stopped):

docker ps -a

Inspect a container in detail:

docker inspect 

2. List and inspect images

List local images:

docker images

Inspect an image:

docker inspect 

3. Build images

Build an image from a Dockerfile in the current directory:

docker build -t : .

Example:

docker build -t my-app:latest .

If the Dockerfile is in another directory:

docker build -t my-app:latest path/to/context

4. Run containers

Run a container in the foreground:

docker run --rm -it :

Run in detached mode (background service):

docker run -d --name  :

Map ports from container to host:

docker run -d --name  -p 8080:80 :

Mount a host directory into the container:

docker run -d --name  -v /host/path:/container/path :

5. Stop and remove containers

Stop a running container:

docker stop 

Remove a stopped container:

docker rm 

Stop and remove in one shot (two commands):

docker stop 
docker rm 

6. Remove images

Remove an image by ID or name:

docker rmi 

Only suggest this when the user is sure the image is no longer needed.

7. Logs and exec

See logs for a container:

docker logs 

Stream logs (follow):

docker logs -f 

Execute a shell inside a running container (if it has /bin/bash):

docker exec -it  /bin/bash

or with /bin/sh:

docker exec -it  /bin/sh

8. Clean up resources

Only suggest these when the user explicitly wants cleanup:

Remove all stopped containers:

docker container prune

Remove unused images:

docker image prune

Remove everything unused (containers, networks, images, and optionally volumes):

docker system prune

For a more aggressive cleanup, but only if the user confirms:

docker system prune -a

Troubleshooting Tips

If images cannot be pulled, check:

- Network connectivity. - Registry authentication (if using a private registry).

If ports are already in use, suggest:

- Changing the host port in -p host:container. - Or stopping the process that currently uses the port.

If a container keeps exiting immediately:

- Suggest checking docker logs for errors. - Inspect entrypoint and command configuration.