Conciseness

The body is lean with no padding of concepts Claude already knows, but the three example patterns ('Bad', 'Good', 'Acceptable Fallback') repeat the same logger.error + json.dumps + response_queue.put skeleton, and the '(Fallback 1008 error if code unknown)' comment is cryptic. Efficient with minor instances that could be trimmed — the 4 anchor, not the fully lean 5.

Actionability

Provides the exact tuple format, executable bad/good/fallback code patterns, a WebSocket callback example, and a concrete 4-step checklist. However, the i18n error-code vocabulary ('API_QUOTA_TIME', 'API_1008_FALLBACK') is referenced but never enumerated, leaving a gap for copy-paste-ready use — mostly executable with minor gaps, so 4 rather than 5.

Workflow Clarity

The 'Checklist for Adding a New TTS Worker' gives a clear, ordered sequence (signature → locate blocks → add puts → encoding) and the core rule is unambiguous with MUST emphasis. There is no verification step confirming the error actually surfaces as a toast in the frontend, a minor validation gap that keeps it at 4; this is not a destructive/batch operation, so the cap-at-3 rule does not apply.

Progressive Disclosure

The body is under 50 lines with well-organized sections (Core Rule, Example Implementation, WebSocket Callbacks, Checklist) and no bundle files exist, so nothing needs external referencing. Per the rubric's simple-skill guideline, this earns a 5 on organization alone.

Specificity

Names the domain and several concrete elements — 'reporting errors from multiprocessing TTS workers to the main process frontend', 'connection errors, quotas, and API limits', 'Toast notifications' — but stops short of a comprehensive action list (e.g., the queue mechanism is only implied). It lists several specific capabilities with minor gaps, matching the 4 anchor rather than the comprehensive 5 anchor.

Completeness

Explicitly answers both parts: the 'what' ('Convention for reporting errors from multiprocessing TTS workers to the main process frontend') and a concrete 'when' ('Use this skill when modifying, adding, or debugging TTS workers in tts_client.py'). This mirrors the 5 anchor's structure of what plus explicit trigger phrases; the 4 anchor requires a 'when' that 'could be more explicit', which does not apply here.

Trigger Term Quality

Good natural keyword coverage — 'modifying, adding, or debugging TTS workers', 'tts_client.py', 'quotas', 'connection errors', 'Toast notifications' — but common variations like 'text-to-speech' spelled out, 'speech synthesis', or 'error handling' are missing. Good coverage with a few natural terms absent, so 4 rather than 5.

Distinctiveness Conflict Risk

Occupies a clear niche — TTS worker error propagation in a specifically named file (tts_client.py) — with distinct trigger phrases, so it is unlikely to fire for unrelated skills. Matches the 5 anchor 'clear niche with distinct triggers; minimal conflict risk'.