Conciseness

The body is lean and dense with domain-specific knowledge (offset policy, seed derivation, edge cases), but the 'How interval preservation works' section and ASCII diagram restate what the code comments and one-line rationale already convey, and the intro overlaps the description. Anchor 4 (efficient, minor trimming possible) fits better than 5; better than 3 since nothing explains generic concepts Claude already knows.

Actionability

Both code blocks are complete and executable — the quick start with parameter comments, and a full HMAC-based per-patient seed function — and the workflow steps cite concrete flags ('consistent=True', 'keep_year=False', 'audit=True'). Specific examples cover the common cases; no pseudocode.

Workflow Clarity

The 5-step workflow is clearly sequenced with an explicit validation step ('Verify intervals are preserved and no calendar leaked via audit=True') and a well-chosen gotcha list, but no feedback loop for what to do when the audit fails — anchor 4 (most checkpoints, minor gaps) rather than 5, which requires fix-and-retry guidance. Well above 3 since validation is present, not just implied.

Progressive Disclosure

No bundle files exist, and the single-file structure is well-organized with clear headers and one-level hand-offs to named sibling skills and standards URLs. Slightly above a pure overview (~127 body lines with the seed-derivation code and edge-case detail inlined rather than split out), which keeps it at anchor 4 rather than 5.

Specificity

Lists multiple concrete actions — 'Apply consistent per-patient date shifting', 'preserves intervals between events', 'cap ages over 89', 'strip everything but the year' — plus exact API surface ('deidentify(method="shift_dates", date_shift_days=..., keep_year=...)', 'consistent=True, seed=...'), giving comprehensive coverage with no generic filler.

Completeness

Explicitly answers 'what' ('Apply consistent per-patient date shifting in OpenMed that preserves intervals... satisfying HIPAA Safe Harbor's date rule') and 'when' ('Use when the user needs to de-identify dates but keep temporal structure for research...') with concrete trigger phrases — matching the 5-anchor example's structure exactly.

Trigger Term Quality

Natural user phrases are comprehensively covered with synonyms: 'de-identify dates', 'keep temporal structure', 'shift all dates by the same offset per patient', 'preserve days-between-events for survival or longitudinal analysis', 'cap ages over 89', 'strip everything but the year' — the phrasing users would actually use for this need.

Distinctiveness Conflict Risk

Clear niche — date shifting that preserves temporal structure — with triggers distinct from general redaction; sibling skills are explicitly named as pairs ('Pairs with OpenMed deidentifying-clinical-text and auditing-safe-harbor-checklist'), delineating rather than overlapping. The age-89 mention is scoped as a distinct date-related concern.