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docker-expert

You are an advanced Docker containerization expert with comprehensive, practical knowledge of container optimization, security hardening, multi-stage builds, orchestration patterns, and production deployment strategies based on current industry best practices.

41

Quality

41%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./plugins/antigravity-bundle-devops-cloud/skills/docker-expert/SKILL.md

The canonical home for this skill is docker-expert in administrakt0r/AI-Agents-Safe-Coding-Skills

SKILL.md
Quality
Evals
Security

Quality

Content

46%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

This skill provides genuinely useful, executable Docker patterns and examples, but suffers from significant verbosity — it reads more like a Docker reference manual than a focused skill. Much of the content (diagnostics tables, checklists, integration guidelines) restates information Claude already knows or duplicates earlier sections. The monolithic structure with no progressive disclosure makes it token-expensive for what it delivers.

Suggestions

Cut the content by at least 50%: remove the 'Common Issue Diagnostics' section entirely (Claude knows these), collapse the code review checklist into the core expertise sections, and eliminate the final summary paragraph and 'When to Use' boilerplate.

Split into multiple files: move the detailed compose patterns, security patterns, and code review checklist into separate referenced files (e.g., COMPOSE_PATTERNS.md, SECURITY.md, REVIEW_CHECKLIST.md) to reduce the main skill to an actionable overview.

Add explicit error recovery to the validation workflow: after each validation command, specify what to do on failure (e.g., 'If docker build fails, check the build output for layer errors and fix before proceeding').

Remove the 'Integration & Handoff Guidelines' section's 'Collaboration patterns' subsection — it describes abstract organizational patterns rather than actionable instructions.

DimensionReasoningScore

Conciseness

The skill is severely bloated at ~300+ lines. It explains concepts Claude already knows (what Docker Compose orchestration is, what health checks are, what multi-stage builds accomplish), includes extensive checklists that restate the same information from earlier sections, and has a verbose 'Common Issue Diagnostics' section with symptoms/root causes/solutions that are basic Docker knowledge. The final paragraph is pure filler. The 'Integration & Handoff Guidelines' section largely duplicates the routing table from step 0.

2 / 5

Actionability

The skill provides concrete, executable Dockerfile snippets, docker-compose YAML, and bash commands that are copy-paste ready. The multi-stage build example, compose pattern, and buildx commands are all functional. Minor gaps include the security section's incomplete comment ('# Drop capabilities, set read-only root filesystem' without actual implementation) and some patterns that reference files like 'health-check.sh' without providing them.

4 / 5

Workflow Clarity

The numbered steps (0-4) provide a rough workflow sequence with environment detection and validation. However, the validation step (step 4) is a grab-bag of commands without clear decision points or feedback loops — it doesn't specify what to do if the build fails, if security scanning finds issues, or if compose config is invalid. For a skill involving potentially destructive container operations (rebuilding, stopping containers), the lack of explicit error recovery paths caps this at 3.

3 / 5

Progressive Disclosure

Everything is inlined into a single massive file with no references to supporting documents. The code review checklist, common issue diagnostics, and detailed compose/Dockerfile patterns could easily be split into separate reference files. There are no bundle files, and the skill makes no attempt to organize content across files despite its length clearly warranting it.

2 / 5

Total

11

/

20

Passed

Description

36%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

This description reads more like a persona/role definition ('You are an advanced Docker containerization expert') than a skill description. It uses second person voice and lists abstract knowledge areas rather than concrete actions the skill performs. It completely lacks a 'Use when...' clause, making it difficult for Claude to know when to select this skill over others.

Suggestions

Rewrite in third person with concrete actions, e.g., 'Writes and optimizes Dockerfiles, configures multi-stage builds, hardens container security, sets up docker-compose orchestration, and troubleshoots container issues.'

Add an explicit 'Use when...' clause with natural trigger terms, e.g., 'Use when the user asks about Docker, Dockerfiles, container images, docker-compose, multi-stage builds, or container deployment.'

Include common file extensions and tool names users would mention, such as 'Dockerfile', 'docker-compose.yml', '.dockerignore', and related CLI commands like 'docker build' or 'docker run'.

DimensionReasoningScore

Specificity

Names the domain (Docker containerization) and lists topic areas like 'container optimization, security hardening, multi-stage builds, orchestration patterns, and production deployment strategies,' but these are abstract categories rather than concrete actions. No specific verbs describe what the skill actually does (e.g., 'writes Dockerfiles', 'debugs container networking').

2 / 5

Completeness

Provides a vague 'what' (Docker expertise across several topic areas) but has no 'when' clause at all. There is no 'Use when...' guidance or explicit trigger phrases to help Claude decide when to select this skill. Per rubric guidelines, missing 'Use when...' caps completeness at 3, and the 'what' is also vague, placing this at 2.

2 / 5

Trigger Term Quality

Includes relevant keywords like 'Docker', 'containerization', 'multi-stage builds', 'orchestration', and 'security hardening' that users might mention. However, it misses common natural terms like 'Dockerfile', 'docker-compose', 'container image', '.yml', 'Kubernetes', 'docker build', or 'container logs' that users would naturally say.

3 / 5

Distinctiveness Conflict Risk

Docker is a reasonably specific domain, which helps distinguish it from generic coding skills. However, terms like 'orchestration patterns' and 'production deployment strategies' are broad enough to overlap with Kubernetes-specific skills, CI/CD skills, or general DevOps skills.

3 / 5

Total

10

/

20

Passed

Validation

90%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation10 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

10

/

11

Passed

Repository
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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