Lesson 2 · 18 min
Installing the program, signing in to your account, and opening it in the folder are three separate steps, each with its own check. The command comes from the official page, the account is your subscription, and no password passes through the terminal.
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Objective: install Git, gh, Node, and the agent (Claude Code or Codex) using cmd, then confirm the version and sign-in method.
Three steps, each with its own check.
Scroll down: each step below lights up its part of the diagram.
Installing puts the program on your computer. It doesn’t connect your account or choose the folder yet. After installing, close cmd and open it again: only the new window can see the program that was just installed.
Like a badge at a turnstile: the terminal sends you to the browser, and that’s where you sign in. Your password never goes through the terminal. Signing in with your account uses your subscription plan; an API key bills usage to a different account.
The agent works in the folder where you opened it. The first time you open it in a folder, it asks whether you trust it: this is your practice folder, so confirm. To exit, /quit in Codex or /exit in Claude Code.
Installed it? Check the version. Signed in? Check the method. Opened it? Check the folder. If something fails, you know exactly which of the three steps stopped.
Right after installing, opening the agent and seeing a sign-in request isn’t a defect: step 1 worked, and step 2 is still needed.
Four precautions that apply to any new program.
“Faster” commands circulate online. A command pasted without checking can run anything.
Read the publisher: Git.Git, GitHub.cli, OpenJS.NodeJS.LTS, @openai/codex, claude.ai/install.cmd. If the name is different or from an unknown page, don’t paste it.
A package with “codex” in its name, but without @openai/ in front.
Paste one command, wait for it to finish, and for > to return. You don’t need to understand the lines that scroll by.
The first time, winget may ask if you accept the source terms: type Y and press Enter.
Successfully installed
Close cmd and open it again. Then git --version, gh --version, and claude --version or codex --version should return a number.
“Is not recognized as an internal or external command” usually just means you’re using an old window.
Installed it? Close and reopen cmd before checking.
The first time you open it, the agent asks you to sign in: use your subscription. In Codex, codex login opens the browser, and codex login status tells you how you signed in.
In the project sheet, record the method (“account” or “API”). Never put the key itself in a sheet, prompt, or screenshot.
Logged in using ChatGPT
Once per computer. Copy one block, wait for it to finish, then close and reopen cmd.
winget install --id Git.Git -e winget install --id GitHub.cli -e winget install --id OpenJS.NodeJS.LTS -e
rem Claude Code: curl -fsSL https://claude.ai/install.cmd -o install.cmd && install.cmd && del install.cmd rem Codex: npm install -g @openai/codex
git --version gh --version claude --version codex --version
codex login codex login status
cd %USERPROFILE%\projetos\meu-primeiro-agente cd claude
C:\Users\ana> winget install --id OpenJS.NodeJS.LTS -e Successfully installed C:\Users\ana> rem closed cmd and opened another C:\Users\ana> npm install -g @openai/codex added 1 package in 9s C:\Users\ana> codex login status Logged in using ChatGPT
Version numbers and times change over time. What matters is seeing a number, not an error message.
codex logout, then codex login.In the Mac or Linux Terminal, install Claude Code with curl -fsSL https://claude.ai/install.sh | bash and Codex with npm install -g @openai/codex (install Node first). Check the same way: run --version in a new window.
Notice what happens when you check in the same window.
Missions
Git.Git).exit).Simulation: actual messages may vary with the Windows and program versions.
Once per computer.
Install Git, GitHub CLI, Node, and the agent you’ll use with winget. Close and reopen cmd, then run the --version commands.
Done when: git --version, gh --version, and claude --version or codex --version show version numbers.
Open the agent, sign in with your subscription through the browser, and note on a card (or phone note) which method is active and where you checked.
Done when: the card says "account" (or "API") and contains no password or key.
The explanation appears after your answer.
Question 1 of 3
You installed Git, and in the same window, git --version replied "is not recognized." What should you do?
Question 2 of 3
In a group, someone shared a “faster” command to install Codex, using a package name other than @openai/codex. What do you do?competency
Question 3 of 3
What do you put in the project sheet about the agent’s access?
Choose an option. The explanation appears after your attempt.