Conciseness

The body is lean, imperative rules with zero explanation of concepts Claude already knows — no 'what an ErrorBoundary is', no library tutorials, no padding. Every bullet encodes a project-specific decision rule ('Never pass `namespace`, `eventId`, `release`, or `captureSource`; the Logger supplies them'), so every token earns its place per the 5 anchor. Not a 4: no instances of over-explanation were found to trim.

Actionability

Fully executable guidance: a copy-paste-ready structured `logger.error` call, the exact `errorKind` vocabulary, concrete source files to read, and exact verification commands (`rg -n "logger\.error"`, `corepack pnpm exec vitest run --config ./vitest.config.ts`, `git diff --check`). Common mapping cases are covered in the body plus the dedicated examples reference. Matches the 5 anchor; not a 3/4 because nothing is pseudocode or missing key details.

Workflow Clarity

The 6-step Required Workflow is clearly sequenced and closes with validation ('Run focused verification and review the diff specifically for diagnostic loss'), reinforced by a Verification section with commands, a manual checklist, and Done Criteria. However, the 5 anchor requires an explicit error-recovery feedback loop ('if checks fail: fix and re-validate'), and the body never states what to do when verification fails — completion is gated on passing but failure handling is only implicit. This is a minor validation gap, so 4 rather than 5; it is clearly above the 3 anchor, which would require missing or merely implicit checkpoints.

Progressive Disclosure

SKILL.md is a well-organized overview (workflow, required shape, field rules, review priorities, verification) with clearly signaled, purpose-conditioned one-level-deep references — 'Read [references/contract.md](references/contract.md) when deciding field behavior, Provider visibility, serialization, or sensitive-data boundaries' and 'Read [references/examples.md](references/examples.md) when migrating legacy calls...'. Both files exist, contain substantive content, and contain no further nested references. Matches the 5 anchor's clear-overview pattern; not a 4 because both pointers are explicit and no content that belongs in references is inlined.

Specificity

The description lists multiple specific concrete actions — 'Enforce Magic Web structured business error logging', 'choose `eventKey/errorKind/error/message/context`', 'preserve historical diagnostics, prevent unsafe payloads', 'verify the JS probe plus `/log-report` behavior' — with comprehensive coverage across adding, changing, migrating, and reviewing. It matches the 5 anchor ('lists multiple specific concrete actions; comprehensive coverage'); it is not a 4 because no action area is missing, and not below because nothing is generic or vague.

Completeness

Both 'what' and 'when' are explicit: what — enforce structured business error logging, choose fields, preserve diagnostics, prevent unsafe payloads, verify probe and `/log-report` behavior; when — 'when adding, changing, migrating, or reviewing `logger.error` calls in `src`, `enterprise/src`, or `customer/src`, including catch blocks, callbacks...'. Explicit 'Use to...' trigger guidance is present, so the completeness cap of 3 does not apply, and the 'when' is concrete rather than the weaker form that would merit a 4.

Trigger Term Quality

Natural trigger terms users of this codebase would actually say are comprehensively covered: '`logger.error` calls', 'catch blocks, callbacks, ErrorBoundaries, workers, WebSocket/storage flows', 'logger adapters', plus exact paths ('`src`, `enterprise/src`, or `customer/src`') and synonyms for the activity (adding, changing, migrating, reviewing). Matches the 5 anchor including file/path-level variations; a 4 would require missing natural terms, and none are evident.

Distinctiveness Conflict Risk

A clear niche with distinct triggers: Magic Web structured error logging tied to specific identifiers (`logger.error`, the structured field set, `/log-report`) and specific directories. It would not plausibly trigger for any other skill, matching the 5 anchor; it is not a 4 because there is no meaningful overlap with adjacent skills — the domain, fields, and paths are unique to this purpose.