Every time I gave my AI assistant "memory," I ended up in the same place: the memory lived in someone else's database, as embeddings I couldn't read, in a cloud I didn't control. Cancel the subscription and the memory goes with it. That felt backwards.
So I built the opposite. It's called Vellum, it's open source (MIT), and the whole idea fits in one sentence:
Point your agent at a folder of markdown. It reads and writes notes over MCP. The folder stays flat files you own.
What it actually is
Vellum is a small, self-hosted MCP server over a plain directory of .md files. Any MCP client (Claude, Cursor, ChatGPT desktop, the MCP Inspector) connects to it and can list, read, write, patch, search, tag, and backlink your notes. Every note is also exposed as a first-class MCP resource (vellum://note/{path}), so your agent can attach a note as context straight from its resource picker, no tool call, no copy-paste.
