Starting From Scratch

Two pieces of software, one command, and a folder on your own disk. This is the actual beginning, and it takes about twenty minutes.

First in Start Here — the short series that gets you from nothing to a working setup.

You’ve seen the demos. Someone shows an AI reading their notes, drafting in their voice, remembering a decision from three months ago. It looks like magic, and the demo always starts at the result. Nobody films the beginning.

This is the beginning.

What a second brain actually is

An external place where your thinking accumulates instead of evaporating. Notes, documents, project files, a daily journal — anything you might need again, in one place, with enough structure that you can find it.

That idea is decades old. Zettelkasten, Getting Things Done, PARA: all systems for keeping knowledge outside your head. They all run into the same wall, which is that maintaining the system is work. Filing, linking, remembering what you called things. Most people set up a notes app, use it keenly for a month, then quietly stop, because the upkeep costs more than the recall is worth.

What changed is that the upkeep is now something you can hand over — not to a chatbot you paste things into, but to an assistant that lives in the folder your notes are already in, reads every file and writes new ones. The filing and the searching move off your plate.

I started mine in late 2025 with an empty folder and an assistant that could see it. Everything since has been layers on that.

The two pieces

You need a place for the knowledge and an assistant that can reach it.

Obsidian is the place. It’s free, and it keeps everything as plain text files in a normal folder on your computer. No proprietary format, no database. If Obsidian vanished tomorrow your notes would still be sitting there, readable in any text editor. That matters more than it sounds, because the whole arrangement depends on an assistant being able to open your files directly — which it cannot do if they’re locked inside someone else’s app.

Claude Code is the assistant. It runs where your files are, so it reads them, edits them, creates new ones and searches across the lot. It does need a paid Claude plan; the free tier doesn’t include it.

Two things worth knowing, because most write-ups you’ll find are out of date on both:

You don’t need Node.js any more. Older guides — including one I wrote — tell you to install that first and then use npm, a tool for installing developer packages. The current install is one line that brings everything with it:

curl -fsSL https://claude.ai/install.sh | bash

And you don’t have to use the terminal at all. There’s a desktop app that runs the same thing in a normal window with buttons. If a black screen and a blinking cursor is why you’ve put this off, that reason is gone.

Your first session

Open your new Obsidian folder, start Claude Code in it, and ask it three things:

What files are in this vault?

Create a note called “First Note” with today’s date and one line saying this is where it started.

Read First Note.md back to me.

That’s the whole first session. It sees your files, it creates one, it reads it back. Unimpressive, and also the entire foundation — everything else is capability stacked on top of an assistant that can already reach your notes.

Making it repeatable

The one thing I’d do differently, knowing what I know now, is write the instructions down on day one instead of month three.

Every new session starts with no memory of the last one. So you tell it the same things about your setup, over and over, until you get bored and stop bothering — at which point it starts guessing. The fix is a file in the folder that it reads every time. A skill, in this context, is nothing more exotic than that: a text file of instructions, in plain English, not code.

Mine started as five lines. Yours can start as three:

About this vault:
- This is my personal notes folder. Everything is markdown.
- Daily notes go in a folder called Daily, named YYYY-MM-DD.
- Ask before creating folders. Never delete a file without
  telling me.
- If you can't find something, say so. Don't guess at a
  filename.

Save that as CLAUDE.md in the folder. From then on, every session begins already knowing where things go — and the last two lines will save you more grief than the first two, because an assistant that guesses confidently is the one failure mode you’ll actually notice.

Next in this series: what to put in that folder, and how those three lines grow into the file that teaches an assistant your whole system.

Twenty minutes, two installs, one file of instructions. Everything else here is built on that.