Conciseness

The body runs ~700 lines / ~31k tokens, with the same guardrails restated many times: the read-side ConditionExpression rule appears in Fact #4, Data modeling #14, and Security #1; the four live-validation facts and two-phase teardown protocol each appear in three places; and vector-search rules repeat across Fact #10, Mechanics #7, Integration #8, the glossary, and Security #6. This is noticeably beyond the anchor-3 "some unnecessary explanation or could be tightened" — it matches "several unnecessary explanations or padded sections" — though it avoids a 1 because nearly all of the content is non-obvious, proprietary DynamoDB knowledge rather than concepts Claude already knows.

Actionability

Guidance is fully executable throughout: a stage table with exact copy-paste commands for all six stages, a complete runnable dedupe handler in Python, literal refusal/offer text to emit verbatim ("pip install boto3>=1.34", the mode-selection question, the teardown confirmation reply), a concrete JSON diff example, and exact preconditions with specific error strings. This is the anchor-5 "copy-paste ready code or commands; specific examples cover the common cases," clearly above the 4 anchor's "minor gaps."

Workflow Clarity

The pipeline is staged and numbered with an at-a-glance table, consent gates before any AWS spend, and dense validation checkpoints: freshness verification of perf_summary.json against launch time, config-match verification before reporting, the two-part skew-vs-starvation gate before attributing throttles, four enumerated refusal preconditions, and the two-phase attested teardown. Feedback loops (re-run on stale data, fix model and re-cost, iterate levels) are explicit everywhere — the anchor-5 pattern, not the 4 anchor which allows "minor validation gaps."

Progressive Disclosure

All six reference files and eight scripts referenced in the body exist in the bundle, references are one level deep (no reference points to another reference), and each carries an explicit read-when/skip-when condition (e.g., "Read this the first time you produce a cost estimate... Skip it for non-cost questions") — matching good structure with clear navigation. It falls short of the 5 anchor because substantial self-contained protocols (the full live-validation workflow and iterative design loop) are entirely inlined in SKILL.md rather than split out, leaving the main file an overview-plus-two-long-manuals; it is above the 3 anchor because the references that do exist are clearly signaled and correctly placed.

Specificity

The description enumerates many concrete capabilities — "enumerates access patterns, chooses partition/sort keys and GSIs, decides single-table vs. multi-table, configures Streams, Global Tables, TTL, vector indexes... and zero-ETL integrations to OpenSearch/Redshift/SageMaker Lakehouse," plus "a monthly cost estimate and optional live validation" — comprehensive coverage with no generic filler. This matches the anchor "Lists multiple specific concrete actions; comprehensive coverage"; it is well above the 4 anchor ("minor gaps in coverage") because design, review, debugging, costing, and validation are all explicitly named.

Completeness

Both questions are answered explicitly: the "what" opens with "Designs, reviews, and debugs DynamoDB data layers... produces a defensible data-layer design with a monthly cost estimate and optional live validation," and the "when" is a concrete trigger clause — "Applies whenever a user is designing, reviewing, or refactoring anything backed by DynamoDB... even when they don't say 'axioms' or 'design review.' Also applies when debugging hot partitions, throttling..." This is the anchor-5 pattern (clear what AND when with concrete trigger phrases), not the 4 anchor where the when "could be more explicit."

Trigger Term Quality

Natural trigger vocabulary is thorough and includes synonyms and user-side phrasings: "schemas, access patterns, GSIs, single- vs. multi-table choices, Streams consumers, transactional outboxes, Global Tables, zero-ETL pipelines," "storing embeddings and running semantic/vector similarity search," and debugging terms "hot partitions, throttling, unbounded Scans, LWW conflicts, or surprise bills." These are exactly the words a DynamoDB user would say, matching the comprehensive-synonyms anchor rather than the 4 anchor's "a few natural terms missing."

Distinctiveness Conflict Risk

Every trigger is scoped to DynamoDB by name, with service-specific terms (GSIs, Global Tables, SearchVectors, zero-ETL) that no general database, document, or AWS-wide skill would claim — a clear niche with minimal conflict risk. It sits at the 5 anchor; the 4 anchor ("minor overlap risk with closely related skills") would apply only if it also matched, e.g., a generic SQL or OpenSearch skill, which the explicit DynamoDB scoping prevents.