Conciseness

The body is dense and token-efficient — argument, output, and error tables with no explanation of concepts Claude already knows — but the 'Input Validation' section (~lines 154-172) restates the 'When to Use'/'When Not to Use' scope almost verbatim, which is duplicative padding that could be trimmed. Not level 5 because of this redundant scope restatement; not level 3 because the rest of the document is lean with every table earning its place.

Actionability

Fully executable guidance: a complete copy-paste Rscript invocation with all flags, a full argument table with types and defaults, concrete input-format examples, error codes with solutions, and a validated test-path command. Not level 4 because the commands cover the common cases end-to-end with no missing key details.

Workflow Clarity

The 4-step workflow includes an explicit validation checkpoint ('Inspect run_record.txt and output_manifest.txt after each run, including failed validation attempts'), and the Error Handling section provides a feedback loop (error code → solution → 'If the error persists, READ: references/troubleshooting.md'). Not level 4 because checkpoints and error-recovery loops are explicit, not merely implied; the destructive/batch cap does not apply since payload preservation and failure recording are validated.

Progressive Disclosure

Good structure overall: a 'When to Read External Files' table clearly signals one-level-deep references (algorithm.md, troubleshooting.md, cli-guide.md — all real files) with purposes, and the body stays an overview. Not level 5 because the body, the argument defaults, and the Testing section reference tests/data/ and tests/run_tests.R paths that are not present in the actual bundle, so key referenced navigation targets are broken.

Specificity

Multiple concrete actions are named: 'estimating relative immune cell infiltration', 'nu-SVR deconvolution workflow based on an LM22 signature matrix', 'comparing one case group against one control group', and 'generating structured tables plus immune-fraction plots' — comprehensive coverage of the skill's capabilities. Not level 4 because there are no minor gaps in coverage; every core capability of the workflow is explicitly enumerated.

Completeness

Both questions are explicitly answered: the 'what' is the deconvolution/comparison/plotting workflow, and the 'when' is a concrete 'Use when...' clause listing trigger conditions, plus a 'NOT for...' clause bounding scope. Not level 4 because the 'when' is fully explicit with concrete trigger phrases rather than merely present.

Trigger Term Quality

Natural user phrasing is comprehensively covered: 'immune cell infiltration', 'bulk expression matrix', 'CIBERSORT', 'deconvolution', 'LM22', 'case group', 'control group', plus exclusion triggers like 'single-cell RNA-seq' and 'spatial' that users would also say. Not level 4 because no commonly used synonym for this task is missing — these are exactly the terms a bioinformatics user would naturally say.

Distinctiveness Conflict Risk

A clear niche (local CIBERSORT-style LM22 deconvolution with case-vs-control comparison) with explicit negative triggers ('NOT for single-cell RNA-seq, spatial data, clinical diagnosis, or workflows that require the original hosted CIBERSORT web service') minimizing wrong-skill activation. Not level 4 because the exclusions leave virtually no overlap risk with adjacent skills.