A Practical Guide to Choosing the Right Memory Substrate for Your AI Agents

Key Takeaways Don't conflate interface with substrate. Filesystems win as an interface (LLMs already know how to use them); databases win as a substrate (concurrency, auditability, semantic search). For prototypes, files are hard to beat. Simple, transparent, debuggable—a folder of markdown gets you surprisingly far when iteration speed matters most. Shared state demands a database. Concurrent filesystem writes can silently corrupt data. If multiple agents or users touch the same memory, s...