This a good example of a novel where things happen around the main character instead of the main character actively making things happen. Essentially, Agnes Grey becomes a governess because her family is in dire financial straits and being a woman, her options are pretty limited. The novel follows her experience with spoiled children and unbearable parents (it’s not just a modern phenomenon, as it turns out).
There’s speculation that this novel is based on Anne’s experiences as a governess herself since she worked as one for a few years becoming a writer and I definitely see it. Only a person who experiences how terrible children can be can describe it in such a way. If these indeed reflect her experiences, I feel bad for her. The first set of children Agnes had to teach was particularly ugly and I have no idea how anyone could stand it.
In any case, I like it less than Wuthering Heights but scores more than Jane Eyre.