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docker

Docker containerization best practices for building, securing, and deploying containers.

33

Quality

27%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./docker/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

22%

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

This skill reads as a generic Docker best practices checklist that Claude already knows, offering no concrete code examples, executable commands, or step-by-step workflows. It lacks actionability entirely—every point is an abstract recommendation rather than specific, executable guidance. The content would need significant reworking to provide value beyond what Claude can already produce from its training data.

Suggestions

Add concrete, executable Dockerfile examples (e.g., a complete multi-stage build Dockerfile) instead of abstract bullet points like 'Use multi-stage builds to reduce image size'.

Include a step-by-step workflow with validation checkpoints, such as: build image → scan with trivy → test health check → tag and push, with specific commands at each step.

Remove generic advice Claude already knows (e.g., 'use official base images,' 'run as non-root') and focus on project-specific conventions, non-obvious patterns, or organization-specific tooling.

Add concrete docker-compose.yml snippets and specific CLI commands (e.g., `docker build --target runtime -t myapp:$(git rev-parse --short HEAD) .`) to make the guidance copy-paste actionable.

DimensionReasoningScore

Conciseness

The content is mostly bullet points which keeps it relatively compact, but it covers broad, well-known Docker best practices that Claude already knows (e.g., 'use official base images,' 'run containers as non-root user'). Much of this is general knowledge that doesn't add novel value.

2 / 3

Actionability

The entire skill is a list of abstract best practices with no concrete code examples, no executable Dockerfile snippets, no specific commands, and no copy-paste ready guidance. Statements like 'Use multi-stage builds to reduce image size' describe rather than instruct.

1 / 3

Workflow Clarity

There are no sequenced workflows, no step-by-step processes, and no validation checkpoints. The content is organized by topic but never walks through a multi-step process like building, scanning, and deploying an image with verification steps.

1 / 3

Progressive Disclosure

The content is organized into logical sections with clear headers, which provides some structure. However, there are no references to external files, no bundle files, and the content is a monolithic list of tips that could benefit from splitting detailed topics (e.g., security, CI/CD) into separate reference files.

2 / 3

Total

6

/

12

Passed

Description

32%

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

The description identifies the Docker domain but remains at a high level without listing specific concrete actions or providing explicit trigger guidance. It lacks a 'Use when...' clause, which is critical for Claude to know when to select this skill. The broad framing of 'best practices' makes it somewhat generic and potentially overlapping with related DevOps or security skills.

Suggestions

Add a 'Use when...' clause with explicit triggers, e.g., 'Use when the user asks about Dockerfiles, container images, docker-compose, multi-stage builds, container security, or deploying containers.'

List specific concrete actions instead of broad categories, e.g., 'Write and optimize Dockerfiles, configure multi-stage builds, scan images for vulnerabilities, set up docker-compose configurations, manage container registries.'

Include common file extensions and tool names users would mention, such as 'Dockerfile', 'docker-compose.yml', '.dockerignore', 'Docker Hub', to improve trigger term coverage.

DimensionReasoningScore

Specificity

Names the domain (Docker containerization) and mentions broad action categories (building, securing, deploying), but does not list specific concrete actions like writing Dockerfiles, multi-stage builds, image scanning, or compose configurations.

2 / 3

Completeness

Describes what at a high level (Docker best practices for building, securing, deploying) but completely lacks a 'Use when...' clause or any explicit trigger guidance for when Claude should select this skill. Per rubric guidelines, a missing 'Use when...' clause caps completeness at 2, and the 'what' is also weak, so this scores a 1.

1 / 3

Trigger Term Quality

Includes 'Docker', 'containerization', 'containers', 'building', 'securing', 'deploying' which are relevant keywords, but misses common variations users would say like 'Dockerfile', 'docker-compose', 'container image', 'Docker build', '.yml', 'Kubernetes', or 'container registry'.

2 / 3

Distinctiveness Conflict Risk

Docker/containerization is a reasonably specific domain, but 'best practices' is vague and could overlap with DevOps, CI/CD, cloud deployment, or security-focused skills. The broad scope of 'building, securing, and deploying' could conflict with multiple adjacent skills.

2 / 3

Total

7

/

12

Passed

Validation

100%

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

Validation11 / 11 Passed

Validation for skill structure

No warnings or errors.

Repository
mindrally/skills
Reviewed

Table of Contents

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