docker

A guide for running Docker locally, where Docker packages applications and their dependencies into isolated containers. It covers containers, images, Compose application stacks, and Docker Desktop.

In plain words
What is it for?
Use it to check Docker, start Docker Desktop, run or stop containers, view logs, open a shell inside a container, inspect resources, manage Compose stacks, and clean up unused Docker data.
Why use it?
It provides the commands and checks needed to run, inspect, troubleshoot, and clean up local Docker environments. This avoids guessing at the correct command for a container or Compose project.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/hamchowderr/braynee/docker
Any agent
npx skills add hamchowderr/braynee --skill docker
Clone the repo
git clone --depth 1 https://github.com/hamchowderr/braynee

Made for: Claude Code, Codex.

Per session 91 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,082 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00091 $0.01082
Opus 5 $0.00046 $0.00541
Sonnet 5 $0.00018 $0.00216
Haiku 4.5 $0.00009 $0.00108

Measured yesterday against content hash 7178ba4996ed, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

docker scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/docker/SKILL.md · 102 lines

How it starts

The opening of the file, as written. The whole thing — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Docker — local dev ops

Drive Docker from the terminal for everyday dev work: containers, images, Compose stacks, Docker Desktop lifecycle, and cleanup. Everything is docker … (Compose is docker compose, Desktop is docker desktop).

Scope: local CLI ops only. This does not wire up Docker's MCP servers — Docker ships its own Claude Code plugin for that (docker/claude-pluginsdocker-mcp-toolkit, or docker mcp client connect claude-code). Full command catalog, networks/volumes, and troubleshooting are in reference.md.

First — is the daemon up?

docker info >/dev/null 2>&1 && echo "Docker running" || echo "Docker NOT running"
docker desktop status            # Docker Desktop state
docker desktop start             # start Desktop if it's down

Containers

docker ps                        # running
docker ps -a                     # include stopped
docker run --rm -it IMAGE        # throwaway interactive container
docker logs -f NAME              # follow logs
docker exec -it NAME sh          # shell in (try bash if sh missing)
docker stop NAME && docker rm NAME
docker inspect NAME              # full config/state JSON

Images

docker images                    # list
docker build -t NAME:TAG .       # build from ./Dockerfile
docker pull IMAGE:TAG
docker rmi IMAGE                 # remove

Compose (multi-container stacks)

docker compose up -d             # start detached
docker compose ps                # stack status
docker compose logs -f SERVICE   # follow one service
docker compose down              # stop + remove (add -v to also drop volumes)
docker compose up -d --build SERVICE   # rebuild + restart one service

Docker Desktop lifecycle (docker desktop)

docker desktop status | start | stop | restart
docker desktop update            # apply updates
docker desktop engine ls         # (Windows) list container engines

Free up space (safe → aggressive)

docker system df                 # what's using space
docker container prune           # remove stopped containers
docker image prune               # remove dangling images
docker system prune              # stopped containers + dangling images + unused nets
docker system prune -a --volumes # AGGRESSIVE: also unused images + volumes

Always warn before prune -a --volumes — it deletes unused images and volumes (data loss). Confirm with the user first.

Read the full file on GitHub · 102 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 102 lines · 91 tokens per session scan A 7178ba4996ed

Subscribe to this mod's changes

docker is a skill published in the GitHub repository hamchowderr/braynee (2 stars, last pushed 5d ago), licensed MIT. It adds 91 tokens to every session and 1,082 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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