Conciseness

The body is lean — bullet-style rules, no explanations of concepts Claude already knows, and every line carries operational value. Minor duplication exists: the preferred paths ('allele', 'cell', 'allele/download') appear in both 'Operating rules' and 'Execution behavior', and the 'Execution' example repeats the first 'Common IPD pattern' verbatim.

Actionability

Fully executable guidance: a copy-paste-ready bash command piping a concrete JSON object into 'scripts/rest_request.py', an exact base_url, and three complete request patterns covering the common cases (browse alleles, query by name, list cells). Input/output contracts are fully specified down to field names.

Workflow Clarity

This is a simple, single-purpose skill (under 50 lines) and the single action is unambiguous: build the JSON input, pipe it to 'scripts/rest_request.py', and summarize the returned records. The Output section even defines the failure shape ('ok=false with error.code and error.message') as a checkpoint, and there are no destructive or batch operations that would require validation steps.

Progressive Disclosure

The skill is under 50 lines with no need for external references, and the body explicitly states 'No additional runtime references are required; keep the import package limited to this file and scripts/rest_request.py' — and that referenced script exists at scripts/rest_request.py. Sections are clearly organized and easy to navigate.

Specificity

The description names the domain ('public IPD query API') and concrete objects ('HLA allele and cell-level metadata') but covers only one action — submitting compact REST requests — leaving the coverage non-comprehensive (no mention of querying, filtering, or downloading, which the body actually supports).

Completeness

Both parts are present: a clear third-person 'what' ('Submit compact IPD REST requests for HLA allele and cell-level metadata using the public IPD query API') and an explicit 'when' ('Use when a user wants concise IPD summaries'). The 'when' clause is somewhat narrow and could name more trigger scenarios such as browsing or searching HLA alleles.

Trigger Term Quality

Good natural keywords for the niche — 'IPD', 'HLA', 'allele', 'cell-level metadata', 'IPD summaries' — that a user in this domain would plausibly say. A few natural variations are missing (e.g., 'IPD-IMGT/HLA', 'immunogenetics', 'query alleles'), so it is not comprehensive.

Distinctiveness Conflict Risk

The IPD/HLA immunogenetics niche is highly specific with distinct triggers ('IPD', 'HLA allele', 'cell-level metadata'); it is unlikely to fire for the wrong skill since virtually no other skill would use these terms.