Brain is the most beautiful way to access a bunch of markdown files.
Is it an LLM wiki, or your personal information collection? Both, really — Brain is a desktop app (Tauri + React) that turns a folder of markdown files into a fast, keyboard-first writing and thinking environment, with AI woven in where it actually helps instead of everywhere at once.
It's highly opinionated by Paul — built around one workflow: Ideate → Write → Review, on top of your own files, in your own workspaces.
⬇ Download Brain v6 for macOS (Apple Silicon + Intel)
Signed and notarized by Apple — open the DMG, drag Brain into Applications, done.
Command line. Brain ships a brain launcher inside the app bundle. Link it into your
PATH once:
ln -s /Applications/Brain.app/Contents/Resources/bin/brain /usr/local/bin/brainThen brain ~/notes opens (or switches to) that folder as a workspace, and brain alone just
opens the app. If Brain is already running, the folder is handed to the running instance.
Workspaces & files. Point Brain at any folder on disk and it becomes a workspace — a plain tree of markdown files, no proprietary format, no lock-in. Add as many workspaces as you like and switch between them instantly.
Three writing modes, switchable per file with ⌘1 / ⌘2 / ⌘3:
-
Ideate — a research agent sits next to your draft, chats about angles, open questions, and sources, grounded in the file you're actually working on.
-
Write — a clean, distraction-free markdown editor for getting the draft down.
-
Review — run your draft past specialized AI agents (Copy Editor, Line Editor, Structural Editor, Tone Coach, Creative Reviewer), each with a narrow focus. Suggestions come back as inline edits and hints you accept or reject one at a time.
Command palette (⌘K) — jump to any file or action without leaving the keyboard.
| Shortcut | Action |
|---|---|
⌘K |
Open command palette |
⌘N |
New file |
⌘⇧N |
New folder |
⌘W |
Close file |
⌘⇧R |
Rename the selected file (or folder) — double-clicking a name works too |
⌘1 / ⌘2 / ⌘3 |
Switch to Ideate / Write / Review mode |
⌘⇧1 / ⌘⇧2 / ⌘⇧3 |
Set editor width: narrow / normal / full |
⌘D |
Toggle the workspace/folder tree |
⌘⇧D |
Toggle the file list column |
⌘J |
Toggle the right sidebar |
⌘⇧F |
Toggle fullscreen |
⌘+ / ⌘- / ⌘0 |
Increase / decrease / reset app font scale |
pnpm install
pnpm tauri dev # run the desktop app
pnpm test # run the test suite