kevin-hs-sohn/hipocampus

Maintains a ~3K token topic index (ROOT.md) auto-loaded each session that compresses conversation history into a scannable overview, letting agents recognize cross-domain connections without explicit search. Uses a self-compacting hierarchical tree (raw → daily → weekly → monthly → root) that applies LLM summaries only above configurable thresholds, preserving detail while managing token growth. Integrates directly into Claude Code and OpenCode via plugin architecture, with hybrid search combining BM25 and optional vector search (qmd) for both keyword and semantic retrieval.

12 stars and 3,942 monthly downloads. Available on npm.