Names the domain (Google Sheets) and one specific action (append a row), but only describes a single capability rather than listing multiple concrete actions.

Describes what it does (append a row to a spreadsheet) but has no 'Use when...' clause or any explicit trigger guidance for when Claude should select this skill. Per rubric guidelines, missing 'Use when' caps completeness at 2, and the 'what' is also minimal, so this scores a 1.

Includes 'Google Sheets', 'append', 'row', and 'spreadsheet' which are relevant keywords, but misses common variations like 'add row', 'insert row', 'new row', or 'gsheet'.

Specifying 'Google Sheets' and 'append a row' provides some distinctiveness, but could overlap with other Google Sheets skills (e.g., read, update, format) since the scope is narrowly stated without clear boundary triggers.

Every section earns its place — flags table, examples, and tips are all necessary and tightly written. No unnecessary explanations of what spreadsheets are or how APIs work.

Provides fully executable CLI commands with concrete examples covering single-row, multi-row, and specific-tab scenarios. The flags table gives all needed parameters with clear descriptions.

This is a single-action command skill, so complex multi-step workflows aren't needed. The caution callout about confirming with the user before executing serves as an appropriate validation checkpoint for a write operation.

Clean structure with prerequisite reference to shared auth skill, well-organized sections, and clear 'See Also' links to related skills — all one level deep with no nesting.