An interesting, good introduction to what philosophy entails as a learnable, improvable skill. (This sentence already poses the question - what do I mean by "good"? So let me correct myself: an understandable, slow introduction keeping in mind the beginners, yet still being thorough.)
We receive advice on how to interact with philosophical work, on how we can ourselves write such essays. It introduces us to the validity of arguments, and what kind of argumentation errors we can encounter - especially ones posing as valid arguments: the frogs, as it calls them. Obviously, we do not get an exhaustive primer on argumentation and logic, as that is outside of the bounds of this book.
On the last few pages we can even find puzzles through which we can flaunt our philosophical and argumentative prowess - which will not be too impressive based on the contents of this sole book.
Still, a good introductory work. (For the definition of "good", see the beginning of my review.)