The Folder: Where You Open It Decides What It Works On

In short

Claude Code works inside the folder you open it in. That folder is its studio.
Opening it in the wrong place is day-one mistake number one.
For your first time: a small, new folder with just the experiment in it.
Huge folder = slower, pricier, more things it can touch by accident.

The folder is the studio

Think back to the collaborator. When they walk in, they walk into one specific room: the one you let them into. What's in that room, they can see and work on; what's in other rooms doesn't exist for them.

With Claude Code it works the same way: the folder you open it in is its workspace. That's where it looks around to understand what's going on, and that's where it gets to work.

It's not some hidden setting you tweak: opening it there is the gesture itself.

In the desktop app — open the Code tab, choose Local (meaning: work on my computer, on my files), then the folder icon right next to it. The Mac's folder picker opens: whatever you choose there is the studio.
From the terminal — it's the folder you're in the moment you type claude. No picker screen: it's just wherever you are.

The Mac folder picker open from Claude Code: the empty NUOVO PROGETTO folder at the top, and the New Folder, Cancel, and Open buttons at the bottom. — The «New Folder» button, bottom left, is the one you need the first time: it builds you an empty studio on the spot.

The classic first-day mistake

The temptation is: "I'll just open my whole Documents folder, so it has all the context and understands better." That's the opposite of what you need, for three reasons:

It takes longer. Before it can work, it looks around. In a massive folder, looking around becomes a job in itself.
It costs more. Every lap it spends exploring is work you pay for — it's the same arithmetic as the lesson on your bill.
It's riskier. The more it has within reach, the more it can touch by accident. We'll see how to set boundaries in the permissions lesson, but the first boundary is not letting it in where it doesn't need to be.

How to get it right

For your first experiment: create a new folder, drop two or three test files in it, and open Claude Code there. If something goes wrong, all you've lost is a test folder.
For real work: open it on the folder for that work, not on the container above it.
If you realize you're in the wrong place, don't push through: close it and reopen it in the right folder. It costs you ten seconds.

What's next

Now you know where to open it. Before you give it your first task, let's settle a debt from the last chapter: you know which engine to pick, but you've never actually seen how to switch it. That's the next lesson, and it's a single gesture.

Did you get it?

Two minutes, no grade. Trying to answer — even getting it wrong — cements the concepts far more than rereading. Not in the mood? Skip it: the lesson still counts as complete.

What determines the folder Claude Code opens in?

It's your first time. Where do you open it?

Why does a huge folder cost more?

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