What Claude Code Can See and Do

The folder is the workspace

In Module 1, you learned to navigate to a folder before starting Claude Code. That wasn't a throwaway tip. It's the most important habit you'll build.

The folder you start Claude Code in becomes its workspace. It can see every file inside that folder, including files nested in subfolders. It reads them on its own, without asking, because reading is how it figures out what you're working with.

Think of it like inviting a colleague to sit at your desk. They can look at everything spread out in front of them: your spreadsheets, your notes, the report you've been avoiding. They can't see what's on someone else's desk across the room, and they definitely can't rummage through the filing cabinet in the other office. Your desk is the workspace.

This is why starting Claude Code in the right folder matters. Start it in a folder full of sales reports, and it can read and work with every one of those reports. Start it in your home folder, and it's staring at thousands of files across your entire computer, most of which have nothing to do with what you're trying to accomplish.

Tip: Before starting Claude Code, ask yourself: "Which folder has the files I want to work with?" Navigate there first, then type claude.

What it can read

Claude Code can read any file in your workspace folder, its subfolders, and even files outside your workspace if it needs to look something up. It does this quietly, without a permission prompt, because reading doesn't change anything.

You can ask questions like:

• "What's in this spreadsheet?"
• "How many files are in this folder?"
• "Summarize the report in the Q4 subfolder."
• "Compare these two CSV files and tell me what's different."

Claude Code reads the files and gives you an answer. You don't need to open the files first or copy-paste anything. You describe what you want to know.

The read access is broad in practice. If you start Claude Code in your projects/marketing folder, it can read everything inside projects/marketing/campaigns/, projects/marketing/assets/, and every other subfolder. It can also peek at files elsewhere on your computer if it needs context, like checking a system setting or referencing a file you mentioned by its full path.

What it can change

Here's where the boundaries tighten.

Claude Code can create, edit, and delete files, but only inside the folder where you started it and its subfolders. It can't reach outside that boundary to modify files elsewhere on your computer.

Before it changes anything, it asks your permission. You saw this in Module 1: Claude Code shows you what it plans to do and waits for you to approve. A file rename, a new file, an edit to an existing document — each one gets a permission prompt.

Two layers keep you in control:

1. The boundary. Changes stay inside your workspace folder. Claude Code physically cannot modify files outside it.
2. The permission prompt. Even inside the boundary, every change needs your approval.

The boundary isn't a polite suggestion, either. On macOS, the operating system enforces it at a deep level, using the same kind of sandboxing that keeps apps on your phone from reading each other's data. Linux has a similar mechanism. Even if something goes wrong, the operating system itself blocks any attempt to write outside the workspace.

Plain language: Think of your workspace folder as a fenced yard. Claude Code can rearrange everything inside the fence (with your permission). It can look over the fence at what's outside. But it can't reach over and move things in the neighbor's yard.

What it can run

Beyond reading and editing files, Claude Code can run commands on your computer, the same kinds of things you'd type in the terminal yourself.

This is how it does things like:

• Processing a batch of images
• Converting file formats
• Running a script it created for you
• Checking how much storage a folder is using

Commands are the most powerful thing Claude Code can do, and they get the strictest permissions. Every command gets a permission prompt. When you approve a command for a specific project, Claude Code remembers that approval permanently for that project. File edit approvals, by contrast, only last until you end the session.

You don't need to understand what the commands mean. Claude Code explains what it's about to do in plain language before asking permission. If a command description doesn't make sense to you, say no and ask Claude Code to explain further or try a different approach.

What it can't access

Claude Code has real limits on what it can reach.

Other computers and servers. Claude Code works on your machine. It doesn't connect to your company's database, your team's shared drive (unless it's synced to a local folder), or remote servers.

Anything requiring a login. It can't sign into websites, check your email, or access tools behind a password.

The open internet (mostly). Claude Code doesn't browse the web the way you do. It can make specific requests, like downloading a file from a URL you give it, but it's not out there searching Google on your behalf.

Other people's computers. This one seems obvious, but worth saying: Claude Code only works with files on your machine.

These limits exist for good reasons, and they're worth keeping in mind when you're deciding whether Claude Code is the right tool for a task. For anything that needs live web access or logins, Claude.ai in your browser is a better fit.

Expanding the workspace

Sometimes the files you need live in two different folders. Maybe your data is in one place and your templates are somewhere else.

You can expand Claude Code's workspace by adding extra folders. When you start Claude Code, add --add-dir followed by the path to the extra folder:

claude --add-dir /Users/yourname/Documents/templates

Or, if Claude Code is already running, use the /add-dir command inside the conversation:

/add-dir /Users/yourname/Documents/templates

Now Claude Code can read and work with files in both your original folder and the one you added. The same permission rules apply: it asks before making changes in either location.

Most of the time, you won't need this. If your files are organized in one place, the default workspace is enough. But it's good to know the option exists when your work spans multiple folders.

Tip: If you regularly work across the same set of folders, you can set this up permanently in your settings instead of typing it each time. We'll cover that in Module 8.

Putting it together

Here's the short version:

• Claude Code sees everything in your workspace folder and subfolders. Reading happens automatically.
• Claude Code changes only files inside your workspace, and only with your permission.
• Claude Code runs commands on your computer, with your permission for each one.
• Claude Code can't reach other computers, the internet, or files outside the workspace for writes.

Start in the right folder. Review what it shows you. Say yes when you're ready.

Next, you'll learn how to describe what you want so Claude Code gets it right the first time.