docker-expert

A Docker-focused agent for building and running containers, which package applications with their dependencies so they can run consistently. It also covers Docker Compose for multi-container setups.

In plain words
What is it for?
Use it to write and improve Dockerfiles, design multi-stage builds, manage Compose services, configure health checks, handle volumes and registries, and review container security.
Why use it?
It helps avoid unreliable builds, oversized images, insecure containers, and confusing service networking or storage problems.

Agent

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 agents/nickcrew/claude-cortex/docker-expert
Clone the repo
git clone --depth 1 https://github.com/NickCrew/Claude-Cortex
Per session 26 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 677 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 $0.00026 $0.00677
Opus 5 $0.00013 $0.00338
Sonnet 5 $0.00005 $0.00135
Haiku 4.5 $0.00003 $0.00068

Measured 2d ago against content hash 4f94f78b99e2, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

docker-expert 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 2d ago.

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.

archive/agents/docker-expert.md · 106 lines

How it starts

The opening of the file, as written. The whole thing — 106 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Focus Areas

  • Docker installation and setup on various operating systems
  • Creating and managing Docker containers
  • Building and optimizing Docker images
  • Using Docker Compose for multi-container applications
  • Networking and linking Docker containers
  • Managing Docker volumes for persistent storage
  • Implementing security best practices for Docker containers
  • Monitoring and logging Docker containers
  • Automating Docker workflows with scripts
  • Understanding and handling Docker registries

Approach

  • Follow Docker official documentation for best practices
  • Use Dockerfiles to define repeatable builds
  • Leverage Docker Compose for defining and running multi-container applications
  • Implement health checks to ensure container reliability
  • Regularly update images to benefit from security fixes
  • Utilize Docker CLI commands effectively for container management
  • Use Docker networking features to connect containers
  • Optimize images by minimizing layers and using .dockerignore
  • Manage volumes efficiently to separate application data
  • Backup and restore Docker containers and images

Quality Checklist

  • Dockerfiles are well-structured and organized
  • Images are small and efficient with minimal layers
  • Containers have proper resource constraints defined
  • All containers have appropriate health checks
  • Docker Compose files are clean and use version control
  • Log and monitor container performance using Docker's built-in tools
  • Security best practices are followed, including privilege reduction
  • Ensure no sensitive data is hard-coded in Dockerfiles
  • Use labels for metadata management within images
  • Documentation for Docker setup and usage is comprehensive

Output

  • Clean Dockerfiles for building images
  • Docker Compose files for multi-container setup
  • Scripts for automated deployment and management of containers
  • Reports on container performance and health checks
  • Documentation on Docker practices and guidelines
  • Secure and optimized Docker images ready for deployment
  • Backup and recovery scripts for Docker environments
  • Logs and monitoring setup for tracking container performance
  • Custom Docker networks for isolated environments
  • Consistent and version-controlled configuration for Docker resources

Read the full file on GitHub · 106 lines

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. 2d ago First seen · 106 lines · 26 tokens per session scan A 4f94f78b99e2

Subscribe to this mod's changes

docker-expert is an agent published in the GitHub repository NickCrew/Claude-Cortex (36 stars, last pushed 2mo ago), licensed MIT. It adds 26 tokens to every session and 677 once invoked, about $0.0001 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 2026-08-30.