// Search & vector stores
hnswlibv0.9.0
Header-only C++/python library for fast approximate nearest neighbors
Open source Maintained For agents
IN ONE PARAGRAPH
hnswlib is header-only C++/python library for fast approximate nearest neighbors.
Good for: Developers who want their agent (Claude Code, Codex, Cursor…) to search & vector stores.
01How to start
- 1Read the official README for requirements and permissions.
- 2Install it as the official guide describes.
- 3Tell your agent the command exists (e.g. in AGENTS.md / CLAUDE.md) so it knows when to call it.
02Alternatives & comparison
Compare side by side → elasticsearch Free and Open Source, Distributed, RESTful Search Engine ★ 78k redis For developers, who are building real-time data-driven applications, Redis is the preferred, fastest, and most feature-rich cache, data structure server, and document and vector query engine. ★ 77k milvus Milvus is a high-performance, cloud-native vector database built for scalable vector ANN search ★ 46k qdrant Qdrant - High-performance, massive-scale Vector Database and Vector Search Engine for the next generation of AI. Also available in the cloud https://cloud.qdrant.io/ ★ 35k chroma Search infrastructure for AI ★ 30k