Retrieval GitHub Repositories (2026) · Open Source Tools

Long-term memory runtime for AI agents — plain Markdown as the source of truth, local ranked retrieval, and an independent sleep-time Manage layer. Claude Code and Codex share one store. No API key.

📑 PageIndex: Document Index for Vectorless, Reasoning-based RAG

Fast and Accurate Code Search for Agents. Uses 99% fewer tokens than grep+read

Open-source inference server and production cluster for all the models your agent needs.

Fast, Accurate, Lightweight Python library to make State of the Art Embedding

MTEB: State-of-the-art evaluation of embeddings across languages and modalities

Embedded retrieval library built on Parquet. Fast, efficient, and scalable.

The retrieval layer for production AI systems. Lightning-fast (<10ms) search without vector databases. Built for browser, edge, on-device, and cloud.

Local code search combining BM25, vector similarity, and cross-encoder reranking. Parses 60+ languages with tree-sitter, runs entirely offline, and returns structured results with file paths, line ranges, and symbol metadata. Built in Rust.

~97% token reduction for AI coding sessions — zero deps, 38 languages, MCP server

Rust library for generating vector embeddings and reranking locally!

An open-source, vector-free long-term memory engine for AI agents, achieving SOTA on LoCoMo and LongMemEval with significantly less context.

Durable, file-based long-term memory for AI agents. Five-package plugin family: SDK, CLI, MCP server, Hermes adapter, and a LangGraph BaseStore. No vector database, no embeddings.

Apache Lucene.NET is an open-source full-text search library written in C#, ported from the Apache Lucene project.

Committed to building the world’s most cutting-edge, CJK-first memory module for all mainstream agents. Any issues and PRs are welcome.