Conciseness

The body is dense with domain-specific value Claude cannot infer: exact parameter formats ('chrom-pos-ref-alt (hg38, no "chr" prefix)'), thresholds (CADD ≥30/≥20, gnomAD AF <0.001, REVEL ≥0.75, AlphaMissense ≥0.564), ClinVar star semantics, and the ClinGen classification ladder. Minor repetition between the Pathogenicity Reasoning Framework and the phase sections (CADD thresholds appear twice) keeps it at the score-4 anchor rather than 5.

Actionability

Concrete, copy-paste-ready guidance throughout: exact tool signatures ('ProtVar_map_variant takes hgvs, genomic, or protein_variant'), a worked FAVOR call ('19-44908822-C-T'), exact annotator strings ('clinvar,gnomad3,sift,polyphen2,revel,alphamissense,cadd_exome'), and a full report template. As an instruction-only skill this satisfies the rubric; the minor gap is no worked end-to-end example showing a call and its parsed output, so score 4 rather than 5.

Workflow Clarity

Phases 0–5 plus synthesis are laid out in an ASCII diagram, Phase 0 validates/normalizes input notation before proceeding, ClinGen gene-disease validity is an explicit pre-interpretation gate, and the Fallback Chains section provides per-tool error-recovery loops for every failure mode. This matches the score-5 anchor (clear sequence, validation steps, feedback loops); not a destructive or batch operation, so no cap applies.

Progressive Disclosure

A single-file skill with well-organized section headers and no broken references (no bundle files exist and the body points to none). At ~230 lines, per-tool parameter reference detail and the report template could sit in a references/ file, but there is no monolithic inline bulk. Good structure with a minor organization gap — the score-4 anchor; not 5 because the file exceeds the simple-skill threshold where sections alone would suffice.

Specificity

Six concrete capabilities are named with specific tools: 'ProtVar structural/functional context, ClinVar clinical classifications, gnomAD population frequencies, CADD deleteriousness, ClinGen gene-disease validity, plus FAVOR one-call comprehensive GRCh38 annotation'. Matches the score-5 anchor (multiple specific concrete actions, comprehensive coverage); third person voice is used throughout, so no voice penalty applies.

Completeness

Explicitly answers both: 'what' via the six named capabilities and 'when' via 'Use for variant annotation pipelines, missense effect prediction, and protein-level variant interpretation with functional context'. Matches the score-5 anchor (clear what AND when with concrete trigger phrases); the 'when' clause is fully explicit, so not 4.

Trigger Term Quality

Natural phrases like 'variant annotation', 'missense effect prediction', and 'variant interpretation' are present, but common user phrasings such as 'is [variant] pathogenic', 'HGVS', or 'rsID' are missing. Good keyword coverage with a few natural terms absent — the score-4 anchor, not 5 (synonym coverage incomplete) and clearly above 3.

Distinctiveness Conflict Risk

A clear niche (protein-level functional annotation with named databases) keeps conflict risk low, but 'variant annotation' and 'variant interpretation' overlap with the sibling ACMG classification skill, and the description itself does not state that boundary (only the body does). Mostly distinct with minor overlap risk — the score-4 anchor.