Provides a well-written, clear and complete description of the topic, as described in Wikipedia:How to write a great article. It should be of a length suitable for the subject, appropriately structured, and be well referenced by a broad array of reliable sources. Scholarly analysis of the topic is aptly summarised. Inline citations are essential. It should be well illustrated, with no copyright problems, preferably with free media rather than fair use ones, which are only to be used as a last resort.
An A-Class article should approach the standards for a Featured article (FA), but will typically fall short because of minor style issues. The article may need minor copyedits, but it should be comprehensive, accurate, well-sourced, and reasonably well-written. A peer review should make the article a viable candidate for FA. Assessing an article as A-Class requires a formal written review by more than one impartial reviewer.