Conciseness

The body is lean — no explanations of concepts Claude already knows, just operating rules, exact field lists, and concrete patterns. Not level 5 because of verifiable redundancy: the identical serotonin JSON example appears both under 'Common HMDB patterns' and again in the 'Execution' bash block, and 'base_url=https://hmdb.ca' is stated three times. Not level 3 or below because everything else earns its place.

Actionability

Fully executable guidance: a copy-paste-ready bash command with a complete JSON payload, two concrete request patterns covering the common cases (metabolites and pathways), an exhaustive required/optional field list, and explicit success/failure output shapes. The documented fields were verified against the actual script interface (base_url, path, record_path, max_items, save_raw, raw_output_path all exist in scripts/rest_request.py). It matches the 'fully executable; copy-paste ready; specific examples cover the common cases' anchor.

Workflow Clarity

This is a simple, single-purpose skill (pipe one JSON object to scripts/rest_request.py, return a concise summary) and the single action is unambiguous, so the simple-skill exception applies. The read-only search operations are neither destructive nor batch, so no validation cap applies; failure detection is even documented ('Failure returns ok=false with error.code and error.message').

Progressive Disclosure

The body is under 50 lines, well-organized into six clearly headed sections, needs no external references, and explicitly states 'No additional runtime references are required; keep the import package limited to this file and scripts/rest_request.py' — the single referenced bundle file exists. This matches the guideline that a short, reference-free skill with well-organized sections scores 5.

Specificity

The description names the domain and one concrete action — 'Submit compact HMDB search requests for metabolites, proteins, diseases, and pathways' — with the four entity categories adding specificity, but it covers only a single action (submitting searches) rather than several distinct capabilities like retrieving raw payloads or formatting summaries. It matches the 'names domain and 1-2 concrete actions, but not comprehensive' anchor; it is not level 4 because no additional actions are listed, and not level 2 because the action is concrete and domain-scoped, not generic.

Completeness

Both parts are explicitly present: the 'what' ('Submit compact HMDB search requests for metabolites, proteins, diseases, and pathways') and the 'when' ('Use when a user wants concise HMDB summaries'). Not level 5 because the trigger clause is narrow and partially tautological — it only fires on wanting 'concise HMDB summaries' and misses natural triggers like looking up a specific metabolite or pathway. Not level 3 because an explicit 'Use when...' clause with a concrete trigger phrase exists.

Trigger Term Quality

Natural terms include 'HMDB search', 'metabolites', 'proteins', 'diseases', 'pathways', and 'concise HMDB summaries' — good coverage of the phrasing a user would naturally use. Not level 5 because common variations are missing: no 'lookup', 'look up', 'human metabolome database', or 'query' phrasings. Not level 3 because the keywords go beyond a bare domain mention and span all four content categories.

Distinctiveness Conflict Risk

'HMDB' is a clear, unique niche with distinct triggers covering four specific content categories; no other plausible skill would fire on these terms. It matches the 'clear niche with distinct triggers; minimal conflict risk' anchor exactly.