Conciseness

The spine is command-first and information-dense with no concept tutorials Claude doesn't need, but there are minor trims: the "Per [sf-gh]" citation is repeated before nearly every step, the References section restates links already cited inline, and asides like "Decoupling gives an audit trail and allows re-scanning..." could be tightened. This fits anchor 4 (efficient with minor over-explanation) rather than 5's every-token-earns-its-place.

Actionability

Every step ships copy-paste-ready, executable material: install commands including the no-sudo curl path, syft scan/multi-format output invocations, cosign attest and verify-attestation, grype scan with --fail-on/--only-fixed, pinned DB import, a full GitHub Actions job, and a runnable jq CI gate. This matches anchor 5 (fully executable, covers common cases).

Workflow Clarity

Steps 1-10 are clearly sequenced with cross-references (Step 7 cites Steps 2 and 5; Step 8 cites Step 7), and validation checkpoints are explicit: cosign verify-attestation, inventory accuracy validation via SBOM diff, --fail-on severity gates, and the diff gate that exits 1 with a review message. The anti-patterns table and diff rules-of-thumb act as checklists, matching anchor 5 rather than 4's "minor validation gaps."

Progressive Disclosure

The spine keeps common usage inline and clearly signals one-level-deep references (formats.md, sbom-formats.md, grype-ignore-rules.md, diff-ci-workflows.md — all verified to exist with real content), but 3 of the 7 bundle files (spdx.md, component-types-and-tooling.md, spdx3-profiles-and-tooling.md) are never linked from SKILL.md, leaving them undiscoverable. Good structure with a real organization gap fits anchor 4 rather than 5.

Specificity

"Generates CycloneDX or SPDX SBOMs with Syft from images or folders, scans them with Grype, diffs SBOMs in CI and explains how to choose a format" lists multiple concrete actions naming tools, formats, and inputs with no coverage gaps for the skill's scope. It clearly exceeds the 4 anchor ("several specific actions; minor gaps").

Completeness

Both what ("Generates CycloneDX or SPDX SBOMs with Syft... scans them with Grype, diffs SBOMs in CI") and when ("Use when a team needs SBOMs for compliance (US EO 14028, EU CRA, FDA), SBOM-based vulnerability scanning or drift checks between releases") are explicit with concrete trigger phrases. This matches the 5 anchor exactly.

Trigger Term Quality

Strong natural terms users would say (SBOM, compliance, US EO 14028, EU CRA, FDA, vulnerability scanning, drift checks, CycloneDX, SPDX, Syft, Grype), but common synonyms like the spelled-out "software bill of materials" and file extensions (.cdx/.spdx) are absent. This sits above anchor 3 ("some relevant keywords") but short of anchor 5's comprehensive synonym coverage.

Distinctiveness Conflict Risk

The Syft/Grype SBOM-generation niche with named tools and compliance regimes is mostly distinct, but "SBOM-based vulnerability scanning or drift checks" leaves minor overlap risk with general vulnerability-scanning or trivy-image style skills. Not 3 (the tool-specific triggers are far more distinctive than "works with document files"), not 5 (overlap with sister scanning skills remains).