Conciseness

Quotes: "Preserve the established localization tool unless migration is requested", "Do not infer language from country or persist a locale override the user did not choose" — every line is a directive or project-specific constraint; there is zero padding explaining what Flutter or localization is. Lean and assumes Claude's competence; the one rationale clause ("because localization and layout failures often combine") is brief and load-bearing, so it stays at 5 rather than dropping to 4.

Actionability

Quotes: "Read `pubspec.yaml`, `l10n.yaml`, existing ARB files", "Use ICU plural, select, and placeholder features" — mostly concrete, actionable guidance naming real files and APIs (as an instruction-only skill, code absence is not penalized per the rubric note). Not 5 because the Verification section gives high-level imperatives ("Generate localizations, analyze") without the actual commands (e.g., `flutter gen-l10n`, `flutter analyze`), leaving minor gaps; not 3 because the guidance is specific and executable in intent, not pseudocode-level.

Workflow Clarity

Quotes: "## Inspect ... ## Rules ... ## Verification" — a clear Inspect → apply Rules → verify sequence, with explicit checkpoints ("test representative locales including an RTL locale, long strings, plurals, missing resources", "Run key screens with large text") and a guardrail ("Preserve the established localization tool unless migration is requested"). Not 5 because there is no feedback loop (what to do when analysis or locale tests fail — fix and re-verify), and not 3 because validation steps are explicitly enumerated rather than merely implied.

Progressive Disclosure

The body is a concise overview (~30 lines), and the detailed ICU syntax, formatting, fallback, and RTL-API guidance is appropriately split into a real, one-level-deep bundle file, clearly signaled: "When formatting messages or localization is in scope, follow the [ICU messages and formatting reference](references/icu-messages-and-formatting.md)". The scoping condition on the reference and the verified existence of the file match the anchor-5 pattern of well-signaled, one-level-deep references.

Specificity

Quotes: "Implement or review Flutter localization with gen_l10n, ARB resources, plurals, locale-aware formatting, RTL layout, and locale testing" — multiple named, concrete capabilities (tool name, resource format, plural handling, formatting, RTL, testing) giving comprehensive coverage of the domain. Not 4 because coverage goes beyond 'several specific actions with minor gaps': it names the toolchain, resource type, and both implementation and review modes.

Completeness

Quotes: "Implement or review Flutter localization with gen_l10n..." (explicit what) and "Use for multi-language UI or localization infrastructure; not for arbitrary copy editing" (explicit when, including a negative boundary). Both what and when are clearly and explicitly stated with concrete triggers, matching the anchor-5 example structure.

Trigger Term Quality

Quotes: "Flutter localization", "multi-language UI", "localization infrastructure", "ARB", "plurals", "RTL layout" — good natural keyword coverage a user would plausibly say. Not 5 because common synonyms like "internationalization", "i18n", or "translations/translate" are absent, leaving a few natural trigger phrases missing.

Distinctiveness Conflict Risk

Quotes: "Flutter localization" pins a clear niche, and "not for arbitrary copy editing" explicitly excludes the nearest overlapping use case. Minimal conflict risk with generic editing or writing skills; triggers are distinct to this domain.