Choosing a store

Most agents are well served by a relational database (Postgres) for structured state, conversations, artifacts, versions, users, sharing, plus object storage (S3-compatible) for the large binary content, with the database holding only paths/pointers. Add a vector store only if you adopt semantic search (Chapter 7), and a cache/queue (Redis, a job queue) as scale demands (Chapters 13, 16). Resist the urge to start with a sprawl of specialised stores; a relational DB plus object storage covers a remarkable amount.