Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
Sympathetic, Thoughtful, Self-conscious
Laurence Yep invests Moon Shadow with a lot of heart in a book that also is historically aware and self-conscious about being put forth into literary history. The Afterword is a perfect example of Yep's self-reflective tone as an author since he, you know, directly speaks to the reader as the author. Yep specifically points out that the story is based on a real person and event and that Dragonwings is a fictitious work.