medium severityNeo4j vector indexes, db.index.vector.queryNodes

Vector similarity search scores returned values slightly outside expected [0,1] range (e.g. >1 or <0), leading to unexpected ordering or invalid results in high-dimensional (e.g. 1024+) embeddings used in RAG/AI agents.[Neo4j 5 Changelog](https://github.com/neo4j/neo4j/wiki/Neo4j-5-changelog)

Root cause

Aggregated floating point uncertainty in cosine similarity calculations for large dimensional vectors caused scores to slightly exceed documented [0,1] range in pre-5.20.0 versions.[Neo4j 5 Changelog](https://github.com/neo4j/neo4j/wiki/Neo4j-5-changelog)

Neo4jvector searchcosine similarityfloating pointprecisionindexProvidervector-2.0GDS

Citations

Vector similarity search scores returned values slightly outside expected [0,1] range (e.g. >1 or <0), leading to unexpected ordering or invalid results in high-dimensional (e.g. 1024+) embeddings used in RAG/AI agents.[Neo4j 5 Changelog](https://github.com/neo4j/neo4j/wiki/Neo4j-5-changelog) — medium Severity | Agentifact Bug Library