Tone refers to the overall mood and message of your book. It’s established through a variety of means, including voice, characterization, symbolism, and themes. Tone sets the feelings you want your readers to take away from the story.
Example: No matter how serious things get in The Good Place, there is always a chance for a character to redeem themselves by improving their behavior. The tone remains hopeful for the future of humanity in the face of overwhelming odds.
https://blog.reedsy.com/literary-devices/
Adjectives for tone:
From https://writerswrite.co.za/155-words-to-describe-an-authors-tone/
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