lilliegez
There's no hard and fast rule, but you do need to balance telling your GP about you are effected by you condition(s) and their replaying it word for word back to the DWP, which could be a problem, so less is better tham more.
In terms of content, use the ESA descriptors as a basis for your comments, the ESA Claim Guides may offer examples, hopefully, the GP will use similar terminology if asked by the DWP.
Good luck
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems 
