alpha, so you can tune relevance per query
or per index. As with all queries, load the index first (or open a
session).
The alpha parameter
alpha | Behavior |
|---|---|
1.0 | Pure semantic (embeddings only) |
0.0 | Pure keyword (BM25 only) |
| between | Blends the two; default is semantic-heavy at 0.8 |
Choosing alpha
- Lower
alpha(toward keyword) when queries contain exact identifiers, SKUs, names, or jargon. - Higher
alpha(toward semantic) when queries are natural-language paraphrases. - Tune per index and per intent (returns, billing, onboarding, etc.).
Implementation
Runnable, per-language examples live in the SDK guides:Related
Metadata filtering
Constrain results by document metadata.
Custom embeddings
Bring your own vectors.