there is one guide for physical claims and another for mental health conditions.
Physical guide = 88 pages
Mental = 95 pages.
Both links are on this page.
www.benefitsandwork.co.uk/help-for-claimants/esa1 Also if you look down the left hand side of the web page there are links to the guides for PIP as well as other resources for members only.
Hope this helps. Please let us know if there is anything else.