Conciseness

The body is dense and assumes competence ("Keep recommendations at the Dockerfile, image-build, and runtime-container layer", constraint bullets with no basic-concept explanations). It is not anchor 5 because the "When to use this skill" section repeats the six frontmatter trigger phrases verbatim and the BOUNDARIES bullet restates the Scope section — minor trimming opportunities.

Actionability

Concrete commands are present ("Run `./mvnw compile` or `mvn compile`", "Run `./mvnw clean verify`", "Read `references/706-technologies-containers-docker.md`") and constraints name specific checks (Java version, jlink module graph, base-image policy). It is not anchor 5 because step 3 ("Implement or refactor Docker and container build artifacts following the reference patterns") delegates the core actions without naming the specific artifacts or reference sections to use, and not anchor 3 because the guidance that is present is executable, not pseudocode.

Workflow Clarity

The four-step workflow (assess context → identify constraints → apply changes → verify and report) is clearly sequenced with verification checkpoints (MANDATORY compile before proposing, VERIFY before promoting). It is not anchor 5 because there is no error-recovery feedback loop (nothing says what to do when compile or clean verify fails), and not anchor 3 because validation checkpoints are explicit, not merely implied.

Progressive Disclosure

The body is a lean overview that keeps detail in a single, well-signaled, one-level-deep reference ("For detailed guidance, examples, and constraints, see [references/706-technologies-containers-docker.md]"). The referenced file exists in references/ and contains no further nested references, matching the top anchor for clear overview plus easy navigation.

Specificity

The description enumerates 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". This matches the anchor for multiple specific concrete actions with comprehensive coverage; it is above anchor 4 ("minor gaps") because coverage spans design, runtime, security, and supply-chain concerns with no obvious omissions.

Completeness

It explicitly answers "what" ("framework-agnostic Docker and container image guidance for Java projects" with a concrete topic list) and "when" ("This should trigger for requests such as ..." with six concrete trigger phrases). Both are explicit and concrete, matching the top anchor; it is not anchor 4 because the "when" clause is not merely present but enumerated with realistic trigger requests.

Trigger Term Quality

Natural user-facing triggers are given verbatim ("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") alongside natural keywords and synonyms (Docker, Dockerfile, container image, containerization, jlink, .dockerignore, SBOM). This exceeds anchor 4 ("a few natural terms missing") by covering both the casual phrasings users would say and the specific technical terms.

Distinctiveness Conflict Risk

The niche is clear ("framework-agnostic Docker and container image guidance for Java projects") and it explicitly scopes away overlap ("For framework runtime wiring, defer to the matching Spring Boot, Quarkus, or Micronaut skill"). It is not anchor 4 because the Java-specific, framework-agnostic framing leaves minimal overlap risk with sibling framework or testing skills.