Names the domain (README files in English and Japanese) and the core actions (confirm/execute synchronization, simultaneous updates), but doesn't list multiple granular actions beyond 'confirm and execute sync'.

Clearly answers both 'what' (synchronize English README.md and Japanese README_ja.md) and 'when' (when README is changed, to ensure both language versions are updated simultaneously), with explicit trigger terms listed.

Includes natural trigger terms in both Japanese and English: 'README更新', 'README同期', 'readme sync', plus mentions specific filenames 'README.md' and 'README_ja.md'. These are terms users would naturally say when needing this skill.

Very specific niche: bilingual README synchronization between English and Japanese versions. Unlikely to conflict with other skills due to the narrow scope involving specific filenames and the sync/translation use case.

The content is mostly efficient but includes some elements that could be tightened. The translation lookup table is project-specific and earns its place, but the 'When to Use' section has some redundancy, and the overall structure could be slightly more compact.

The skill provides a clear process with specific check items and a translation table, but lacks executable code—the 'Read README.md' bash block is pseudocode, not an actual command. The diff detection relies on Claude's judgment rather than concrete tooling or commands.

The 4-step workflow is clearly sequenced: detect diffs → report → sync → final validation. Step 4 provides an explicit validation checklist, and the report format in Step 2 shows exactly what output to produce. The feedback loop is implicit but the final check step ensures correctness before completion.

For a skill of this size (~80 lines of content), the structure is well-organized with clear sections (Overview, When to Use, Instructions with numbered steps, Guidelines). No external references are needed, and the content is appropriately scoped without being monolithic.