Conciseness

The ~20-line body is lean, assumes Claude's competence (no explanation of what Convex or an error boundary is), and uses dense, purposeful lines. It falls just short of the score-5 anchor because a few statements are duplicated — redaction is stated in the intro, again as workflow step 3, and again as a rule; 'Data never leaves the user's deployment' appears in both intro and Rules — minor redundancy that could be trimmed.

Actionability

Concrete artifacts are named ('app.use(sentinel)' in 'convex/convex.config.ts', 'convex data', 'run-once-query', the monitor's 'prod_error' event, the 'triage' cron), but nothing is fully executable: there is no install command, no copy-paste snippet for convex.config.ts, and step 2 ('a React error boundary plus window.onerror/unhandledrejection and breadcrumbs') is descriptive rather than runnable. This matches the anchor 'Some concrete guidance but incomplete; pseudocode instead of executable code; missing key details' rather than the mostly-executable bar of score 4.

Workflow Clarity

The five numbered steps form a clear, correctly ordered sequence (install → wire client → redaction defaults → read/react → optional cron) with specific commands at each stage. It sits at 'Clear sequence with most checkpoints present; minor validation gaps' rather than 5 because no explicit verification step exists (e.g., confirming captured errors appear in the table after wiring) — though step 4's read step serves as an implicit check, and no destructive or batch operation triggers the score-3 cap.

Progressive Disclosure

The skill is under 50 lines with no bundle files (references/, scripts/, and assets/ are absent) and no need for external references; content is organized into a clear overview paragraph, a numbered Workflow section, and a Rules section. Per the rubric's simple-skill guidance, this earns the top anchor for well-organized sections with no buried or nested references.

Specificity

The description names the domain precisely ('Sentinel production error capture in your own Convex deployment') but offers only a single action verb, 'Set up', with no mention of the capture pipeline's other capabilities (redaction, reacting to errors, self-healing triage). This matches the anchor 'Names domain and 1-2 concrete actions, but not comprehensive' — score 4 would require several specific actions, score 2 would leave the domain vague, which it is not.

Completeness

The 'what' is stated clearly ('Set up Sentinel production error capture in your own Convex deployment'), but there is no 'Use when...' clause or equivalent explicit trigger guidance anywhere in the description. Per the judging guidelines this caps completeness at 3, matching the anchor 'Has a clear "what" but "when" is missing or only weakly implied'.

Trigger Term Quality

Relevant keywords are present ('production error capture', 'Convex deployment', 'Sentinel') but common variations users would naturally say are missing: 'error monitoring', 'crash reporting', 'log production errors', or the package name '@convex-dev/sentinel'. This fits 'Some relevant keywords but missing common variations or synonyms' rather than the comprehensive coverage of score 4.

Distinctiveness Conflict Risk

The description names a specific product ('Sentinel'), a specific platform ('Convex deployment'), and a specific concern ('production error capture'), giving it a clear niche with minimal overlap risk against generic error-handling or monitoring skills. It clearly matches the anchor 'Clear niche with distinct triggers; minimal conflict risk'.