AI agents need structured data, not similarity search. Graph DBs are expensive, vector stores are fuzzy.
Lithium is a storage engine on PostgreSQL ltree. Hierarchical, versioned, scoped queries. Two commands:
npx @lithium-ai/kit init
claude mcp add lithium -- npx @lithium-ai/kit serve
Your agents get tools to navigate, store, and retrieve structured data on your existing Postgres.
Open source, MIT.