Mood comes from AcousticBrainz, the public mood-classifier project. Your playlist's tracks each get matched against this library — and not every track has a mood classification yet.
When fewer than ~15% of the tracks in the slice you're viewing have mood data, the system tells you so explicitly rather than publishing a misleading average over a tiny sample. This is the honesty layer at work.
Two ways to get mood data flowing:
- Look at a wider slice. Switch to the venue-wide tab — your full library aggregates the few mood-classified tracks across all your playlists into a meaningful signal.
- Mix in established artists. Long-tail and very-new releases are the gap. Adding well-known reference tracks of the same vibe will lift the mood coverage without changing the sound.
The audio-features half of the fingerprint is unaffected — energy, tempo, danceability, valence, and the rest publish regardless of mood coverage.