The command line

A window with no buttons

Kai opens a dark window with a blinking cursor and types npm run dev. Seconds later, Hyper Shards is running in the browser. No menus, no clicking.

That window is a terminal, also called the command line. Instead of clicking buttons, you type commands: short instructions the computer runs straight away. A program you control by typing has a CLI (command-line interface). One you control by clicking has a GUI (graphical user interface).

It looks old-fashioned because it is: people typed commands like these in the 1970s, before computer mice were common. Professionals still use it every day, because one exact command is fast and easy to repeat.

Reading the prompt

When the terminal is ready, it shows a prompt (not the AI kind: here it means "I'm waiting for a command"). On Windows PowerShell it looks like this:

PS C:\Users\kai\studio>

On a Mac it can look like kai@laptop studio %.

The prompt shows which folder you are in right now, called the working directory. Every command you type acts on that folder. Type after the prompt and press Enter.

Bolt says: In examples, don't type the prompt itself. Only type what comes after it.

Moving around folders

Four commands get you almost anywhere:

• pwdPrint working directory. Shows the full path of the folder you are in, like /Users/kai/studio.
• ls or dirLists the files and folders here. ls works on Mac, Linux and PowerShell. dir works in Windows terminals.
• cdChange directory. cd hyper-shards moves into that folder. cd .. moves up one level.
• mkdirMake directory. mkdir sounds creates a new, empty folder called sounds.

Running the game

Our games use a dev server: a small program that serves the game to your browser while you work, and reloads it when you save a file.

Type npm run dev. npm is a tool that comes with Node.js. It opens the file package.json, finds a script called "dev" and runs it. The terminal prints an address like http://localhost:5173. localhost means "this computer".

The dev server keeps running until you stop it with Ctrl+C. Even on a Mac it is Ctrl, not Cmd.

Git lives here too

Git, the tool that keeps save points of our code, is a command-line program. Every Git action is a command that starts with git:

git status shows what changed.
git add . picks the changes to save.
git commit -m "Fix ship sliding" saves them.

The Git buttons in Antigravity 2.0 run these same commands behind the scenes. Knowing the commands means you understand what the buttons really do, and you can fix things when a button can't.

Errors are clues

Red text in the terminal looks scary, but it is a clue. Read it like a detective:

• Find the word error. The useful line is often near the bottom.
• Find the names. Which file, folder or command does it mention?
• Check for typos. gti status gives "command not found" or "not recognized", because the command is git.

Still stuck? Paste the exact error into your prompt for Claude, plus the command you ran.

Bolt says: Press the up arrow to bring back your last command. Press Tab to finish a file name for you.

AI agents use it too

AI agents work in the terminal as well. In Antigravity 2.0, an agent can run npm run dev, read the error output, find the bug and try again, the same loop you just learned.

That is powerful, so we stay in charge. Read every command before an agent runs it. Some commands delete files with no undo and no recycle bin, like rm -rf (remove a folder and everything inside). Never approve one you don't understand.

Bolt says: Agents need a brain to think with. Next lesson: Claude Opus 5.5, the AI model behind our agents.