706-technologies-containers-docker

Use when you need framework-agnostic Docker and container image guidance for Java projects - Dockerfile design, multi-stage Maven builds, jlink custom runtimes, micro runtime distributions such as Alpaquita, JVM container ergonomics, non-root execution, image metadata, .dockerignore, reproducible builds, vulnerability scanning, SBOM awareness, and production-safe container defaults. This should trigger for requests such as Review Java Dockerfile; Improve Docker image security; Add jlink runtime to a Java container; Add containerization to a Java project; Optimize Java container image size; Review Docker build reproducibility. Part of Plinth Toolkit

Quality

89%

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Securityby

Passed

No findings from the security scan

Quality

Content

78%Weight 40%Scale 1-5

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

The content is well-structured and actionable, with a clear workflow, explicit validation gates, and clean progressive disclosure to a single existing reference. Its main limitation is that the concrete Dockerfile/image-build examples live in the external reference rather than the body, and the verify step is described at a high level.

Suggestions

Add 1-2 concrete, copy-paste Dockerfile snippets (e.g., a multi-stage Maven + jlink example) directly in the body so the most common cases are executable without opening the reference.

Tighten or de-duplicate the 'What is covered' bullets and the constraint list, which partially restate capabilities already in the description, to improve token efficiency.

Make the workflow's verify step concrete by naming the exact commands to run (e.g., 'docker build', 'docker scout cves', 'docker run --rm smoke test') with an explicit fix-and-retry loop on failure.

Dimension	Reasoning	Score
Conciseness	The body is mostly lean with bullet structure and no pedagogical padding explaining Docker or JVM basics, but the nine constraint bullets and the 'What is covered' list partially restate capabilities already in the description, leaving minor trimming opportunities. Not a 5 because some content could be tightened without losing clarity.	4 / 5
Actionability	Concrete commands are present ('./mvnw compile', 'mvn clean verify') alongside explicit deferral targets ('@301-frameworks-spring-boot-core') and a real reference file, but the bulk of executable Dockerfile guidance lives offloaded in the external reference rather than as copy-paste examples in the body. Mostly executable guidance with minor gaps.	4 / 5
Workflow Clarity	A clear 4-step sequence (read context, identify constraints, apply changes, verify) with explicit validation gates — MANDATORY compile-before-change and VERIFY before promoting — appropriate for a batch/build operation. Not a 5 because the verify step itself ('Execute appropriate build, image build, scan, smoke-test...') is described abstractly rather than as a concrete validate-fix-retry loop.	4 / 5
Progressive Disclosure	The body is a well-organized overview with a single one-level-deep reference — references/706-technologies-containers-docker.md (which exists) — clearly signaled via a dedicated Reference section and link, with no nested references and detail appropriately offloaded.	5 / 5
	Total	17 / 20 Passed

Description

100%Weight 40%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.

The description is excellent: it states a clear niche, enumerates concrete capabilities, and provides explicit natural-language trigger phrases that answer both what the skill does and when to use it. No significant weaknesses; it would trigger correctly for the intended requests.

Dimension	Reasoning	Score
Specificity	Lists many concrete capabilities — 'Dockerfile design, multi-stage Maven builds, jlink custom runtimes, micro runtime distributions such as Alpaquita, JVM container ergonomics, non-root execution, image metadata, .dockerignore, reproducible builds, vulnerability scanning, SBOM awareness' — giving comprehensive coverage of specific actions rather than vague language.	5 / 5
Completeness	Opens with an explicit 'Use when you need...' clause stating what the skill does and follows with 'This should trigger for requests such as...' listing concrete triggers, clearly answering both what and when.	5 / 5
Trigger Term Quality	Explicit natural trigger phrases users would actually say — 'Review Java Dockerfile; Improve Docker image security; Add jlink runtime to a Java container; Add containerization to a Java project; Optimize Java container image size; Review Docker build reproducibility' — provide comprehensive coverage of natural terms.	5 / 5
Distinctiveness Conflict Risk	The niche is highly specific — framework-agnostic Docker/container-image guidance scoped to Java projects — with distinct trigger phrasing, minimizing overlap with adjacent framework or testing skills.	5 / 5
	Total	20 / 20 Passed

Validation

100%

Warnings & errors only

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

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: jabrena/plinth
Path: skills/706-technologies-containers-docker/SKILL.md
Commit: f6dfc6f

Reviewed: about 2 hours ago

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