You Say Search, I Say Recs: Spotify Agentic Query Understanding

Authors: Spotify Research
Venue: ACM (dl.acm.org/doi/10.1145/3705328.3748127)

Problem

Exploratory search (“new releases for me”, “similar artists to X”) doesn’t fit traditional search — it requires personalized retrieval that lexical/semantic matching alone can’t provide. Recommendation systems handle these better, but traditional search can’t route to them.

System Design

  • LLM router: interprets complex query intent and routes to appropriate downstream service (search API vs. recommendation API)
  • Post-training adaptation: router fine-tuned for production scale
  • Specialized sub-agents: handle specific exploratory intents
  • Search + recommendation APIs: parallel backend services

Results

Use CaseImprovement
Similar artists discovery+115%
New music releases+91%
Broad music searches+25%
Broad podcast searches+15%

Key Insight

The boundary between search and recommendations is blurry — users say “search” but mean “recommend.” An agentic LLM router can identify which intent is truly at play and delegate to the right system.