# Second Brain

A self-hosted memory layer, deployed on a personal Cloudflare account, that stores notes once and makes them retrievable by meaning from Claude, ChatGPT, Cursor or any other MCP-compatible AI tool.

Second Brain gives a set of otherwise disconnected AI tools, such as Claude, ChatGPT, Cursor and Codex, one shared, persistent memory. Instead of repeating the same project details, decisions and preferences in every app, a user stores something once and retrieves it later by meaning rather than exact wording.

It runs entirely inside the user's own Cloudflare account using Workers, D1 and Vectorize, so the data and its retrieval stay under the user's control. A Team Edition adds a shared layer alongside each person's private one: sharing moves a memory into the team layer rather than copying it, its original author stays visible, and only that author or an admin can edit, delete or unshare it. Memories can be captured from MCP clients, a CLI, a browser extension, Obsidian, Notion, calendars, email, iOS Shortcuts or a web dashboard, and reminders can be pushed for memories with a due date.

A desktop app for Mac and Windows sets up the Cloudflare deployment and connects a user's AI tools without a terminal.

Website: https://www.thesecondbrain.dev