Google has updated its Search Quality Rating Guideline and they have released a handbook on the same. This is the first time Google is sharing the Search Quality Rating Guidelines to public.
After the release of basic human guideline on how google works and it looks for webpages, which is published on 2013, this is the full version guideline handbook released by Google. After 2013, lot of updates and changes on the rater guidelines, but Google haven’t shared it publicly. Now Google has completed the major revision of its rater guidelines and shared this full version of Guidelines handbook, which is a PDF document has 160 pages.
You can download it directly from Google here and its free of cost.
However, Google states that this not a final version of search quality rating guideline, the updated version will be released based on the notable changes and updates on search guidelines.