Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
Amused, Ironic, Unforgiving, Empathetic
In the strategy-based Westing game, it's the narrator who holds all the cards—er, chess pieces.
We might think Mr. Westing is smart for designing such a complicated, tricky game, but ultimately the narrator's even smarter: she/he keeps track of the puzzle, the real solution, and each of the heirs' constantly evolving answers.
The narrator always knows things that the characters don't, which sometimes comes out as a delicious irony that's shared only with the reader:
Madame Hoo knew from the shifting eyes that a bad person was in the room. She was the bad person. They would find out soon. The crutch lady had her writing-book back, but all those pretty things she was going to sell, they wanted them back, too. She would be punished. Soon. (24.9)
From time to time the narrator pokes gentle fun at the heirs as they bumble into and around the clues they're given... but she/he can also be almost cruel in stripping away characters' cover ups and shields to reveal the true selves they're hiding:
What good luck, the hobbling Sydelle Pulaski thought. Now she would really be noticed with such a pretty young thing for a partner. They might even invite her to the wedding. She'd paint a crutch white with little pink nosegays. (7.23)
The narrator empathizes with characters who are in bad spots, and gets us readers to feel empathetic too—although our narrator never disguising the prejudiced or hurtful thoughts of the book's characters.