Ash attribute type for vector embeddings, stored as a Neo4j LIST<FLOAT>.
The Elixir-side value is a plain [float()] list, and it is persisted as a
LIST<FLOAT> node property — which is what Neo4j's vector indexes and
vector.similarity.cosine/2 operate on. The native Bolt 6.0 %Bolty.Types.Vector{}
type is a query-parameter wire type and cannot be written as a node
property, so it is never used for storage. cast_input/2 and cast_stored/2
still accept a %Bolty.Types.Vector{} defensively and unwrap it to [float()].
Cypher 25 required
Vector operations require Cypher 25 (Neo4j ≥ 2025.06) — not Bolt 6.0. With
list storage and list query params, similarity search works over Bolt 5.8.
This is an AshNeo4j-level requirement — see AshNeo4j.Cypher.require_cypher25!/0.
Constraints
:element_type—:float32(default) or:float64:dimensions— expected number of dimensions; validated on cast when set
Usage
attribute :embedding, AshNeo4j.Types.Vector,
constraints: [element_type: :float32, dimensions: 1536]See AshNeo4j.Vector for index creation helpers and AshNeo4j.Functions.VectorSimilarity
for cosine similarity filtering/sorting.