"The Nightingale and the Rose" has a descriptive and direct tone. While the story is by no means devoid of emotion, sentiments are expressed solely through speech and thus assigned to characters rather than the narrator. The impersonality of the narrator creates a semi-detached tone that gives the story the timelessness and universality of a fairy tale.
However, although the narrator does not offer any explicit judgement on the characters, the tone of "The Nightingale and the Rose" combines romance and cynicism to help cue readers into where, exactly, their sympathies should lie. Take, for instance, the way the animals in the garden react when they hear the heartbroken Student's woes:
"For a red rose?" they cried; "how very ridiculous!" and the little Lizard, who was something of a cynic, laughed outright. But the Nightingale understood the secret of the Student's sorrow, and she sat silent in the oak-tree, and thought about the mystery of Love.
The contrast of the cynical lizard who scoffs at the Student's melodrama and the idealistic Nightingale who sympathizes with the plight of true love reflects how the tone of "The Nightingale and the Rose" flips back and forth between an idealistic romanticism and a kind of world-weary pessimism. The Nightingale's sacrifice to help the Student, for example, is not presented as ridiculous or foolish but rather written with a sympathy and grandeur that respects the pure selflessness of her deed. However, that the Nightingale's sacrifice turns out to be in vain—with the Student's love in the end looking more like a shallow whim than something that honors the grand "mystery of love"—also vindicates the lizard's cynicism. The tone of "The Nightingale and the Rose" is thus intentionally detached and ambiguous, allowing readers to come to their own conclusions about the story.