Actions12
Hybrid Search
AI-generatedSummary
Searches a vector collection using both semantic similarity and BM25 lexical ranking, then fuses the results using RRF or weighted scoring.
Inputs
- Collection (required) — Collection to search. It must have a BM25 index created by upserting documents with a non-empty Text value.
- Query Vector (required) — Array of finite numbers or a JSON string containing one. Its length must match the dimension configured in the vector store credentials.
- Query Text — Text for BM25 lexical search. Defaults to empty; with an empty query, ranking uses the vector query only.
- Limit — Maximum results to return; defaults to 50.
- Metric — Vector similarity metric: cosine (default), dot product, Euclidean, or Manhattan.
- Mode — Fusion strategy: RRF (default) blends by rank position, or Weighted blends vector and text scores.
- Vector Weight — In Weighted mode, sets the vector score weight; defaults to 0.5.
- Text Weight — In Weighted mode, sets the BM25 score weight; defaults to 0.5.
- RRF K — RRF smoothing constant; defaults to 60 and is used in RRF mode.
- Fetch K — Number of candidates fetched from vector search before fusion. Defaults to 0, which uses the engine default.
Output shape
A list of result items, each containing id, score, and metadata.
Each hit is a separate n8n item; metadata defaults to an empty object. A missing BM25 index causes an error instructing you to upsert documents with a Text value. Errors can be returned as an error item when Continue On Fail is enabled.