Features are fields inside documents produced by feature extractors. They include vectors and payload attributes that power retrieval, enrichment, and analytics.

​
Overview

  • Where features live: Inside collection documents (not standalone). Documents are written by extractors during processing.
  • What features are: Model outputs such as vectors (dense/sparse/multi) and structured payload fields.
  • Configured by: The collection’s feature extractors and index definitions.

​
Feature anatomy (in a document)

A document stores features as payload fields and vectors. Exact paths depend on the collection’s extractor configuration and feature addresses. 
{
  "document_id": "doc_123",
  "collection_id": "col_products_v1",
  "metadata": {"category": "shoes"},
  "features": {
    "text_embedding": {"vector": [0.12, 0.03, ...]},
    "clip_image": {"vector": [0.09, 0.41, ...]},
    "entities": ["shoe", "sneaker"],
    "title": "Red Sneaker"
  }
}
  • Vectors are stored under configured vector field names and indexed per the collection’s vector indexes.
  • Non-vector outputs (payload) are stored as normal document fields under features or other configured paths.

​
Describe features for a collection

Get feature addresses and metadata available in a collection.
  • API: Describe Collection Features
  • Method: GET
  • Path: /v1/collections/{collection_identifier}/features
  • Reference: API Reference

​
Discover feature extractors

Browse supported extractors and their input/output schemas.

​
Used by

  • Retrievers: Execute vector/payload search over features in documents (Retrievers).
  • Taxonomies: Join/enrich using configured feature fields (Taxonomies).
  • Clusters: Build similarity groups over feature vectors (Clusters).

​
Best practices

  • Pick extractors per modality: Text, images, audio, and video often need different models.
  • Version your models: Prefer new collections or reprocessing when changing model versions.
  • Name feature fields clearly: Stable field names simplify retriever and taxonomy configs.

​
See also

Collections

Configure extractors and index definitions

Feature Extractors

Supported extractors and configurations

Retrievers

Search across feature vectors and payloads

Taxonomies

Enrich documents using feature-based joins