The Queen uses her diary for appointments but it is rumoured she puts acerbic reviews against those that do not go well. FNN would love to report on this in more detail but the Queen's diaries are subject to the Fairy Kingdom's equivalent of the Official Secrets Act so all the realm has to go on here are the rumours.
Eileen, while still resident in the magical world, used her diary to keep a record of her daring deeds. She also thought that keeping a historical record of her good deeds fighting dragons and so on would help her defend herself in her fights with the Council!
L'Evallier again keeps his appointments in his dairy but he also grades his using 1 for something he is looking forward to a lot to 10 where he is not looking forward to it at all. Most Council meetings are graded 9 or 10!
Hanastrew keeps a record of "kills" - not to defend herself against the Council. Unlike her mentor, she doesn't tend to land herself in it with them but she likes to know what she removed and when and why. She also uses her diary to prove to that wildlife nut, Fresdian, that everything she has removed was a direct threat to someone. Sometimes that someone is just Hanastrew of course so Fresdian is not entirely impressed by this.