Lesson 6 · 20 min
For a task, an agent can change ten files at once. Without history, you don’t know what changed or how to go back. With Git, each good version is saved with a date and explanation, and you can undo a change you didn’t approve with one command.
Start the lesson
Objective: save versions with status, add, diff, and commit, and undo an agent’s change with git restore, without panicking.
The three stages of a file in Git. Click each one.
Scroll down: each step below lights up its part of the diagram.
The agent created or changed files. git status shows each one: "Untracked files" are files Git isn’t tracking yet; "Changes not staged" are changes that haven’t been staged.
git add with the file name stages only that file for the next version (Git calls this staging). git diff --cached shows, line by line, what will go in.
The commit clips together what was staged. The message is the photo caption: a verb and an object, such as "Add contact section." "update" won’t tell you anything a month from now.
Change not saved yet: git restore returns the file to the last saved version (and discards your changes). Version already saved: git revert creates a new version that undoes the previous one without erasing the history.
Commit before you ask. The agent makes changes. Check them with status and diff. Like them: add and commit. Don’t like them: restore. Each good version becomes a point you can return to.
Git runs only on your computer, without internet. GitHub is another optional step (lesson 8).
Click each step.
Inside meu-primeiro-agente, git init creates the history. Never run it in your entire personal folder.
git config user.name and user.email, without --global, say who saves changes, only in this project. The email appears in each version and is visible if the folder is published.
Initialized empty Git repository in …\meu-primeiro-agente\.git\
git status tells you what stage each file is at. Always run it before staging anything.
This is where the .gitignore from lesson 5 proves itself: .env doesn’t appear in the list.
AGENTS.md, README.md, .gitignore, .env.example… and no .env.
To learn, name the files in git add. The shortcut git add . stages everything that isn’t ignored, including a personal note you forgot in the folder.
git log --oneline shows a short list of versions, one per line.
Creates README, AGENTS.md, and a list of what not to save
Only in the file, not saved: git restore arquivo. In a saved version: git revert with the version code, which appears in the log.
Check the open file, not just the terminal response.
Revert makes a correction and leaves all three versions in the history.
In the meu-primeiro-agente folder. Replace anything inside < >.
cd %USERPROFILE%\projetos\meu-primeiro-agente git init git config user.name "<Seu Nome>" git config user.email "<seu@email.com>" git status
git add README.md AGENTS.md .gitignore .env.example index.html git diff --cached git commit -m "primeira versão" git log --oneline
git status git diff
git restore index.html git status
git add index.html git commit -m "<what changed, with a verb>"
git log --oneline git revert <código da versão>
On branch master
No commits yet
Untracked files:
(use "git add <file>..." to include in what will be committed)
.env.example
.gitignore
AGENTS.md
README.md
index.html"Untracked files" = outside the history. .env is not on the list: .gitignore worked.
cd first and check the path.git config are missing.The agent will change index.html along the way.
Missions
primeira versão.Simulation: codes and counts in the responses are examples.
In the meu-primeiro-agente folder, with the agent open in another cmd window.
git init, config, status, add, and commit. Ask the agent to make a big change to the page and, if you don’t like it, undo it with git restore.
Done when: you undid an agent change with one command, and git status says "working tree clean".
Ask for two small changes and save each with a message that says what changed. Then undo the last one with git revert.
Done when: git log --oneline shows the versions with clear messages, including the revert, and the page is back to how it was.
The explanation appears after your answer.
Question 1 of 4
The agent made a big change you didn’t approve, and you haven’t saved anything since. What should you do?competency
git restore restores the file in one command. That’s why you should commit before asking for a major change.git restore restores the file in one command. That’s why you should commit before asking for a major change.Review: Rehearse: save, break, and go backQuestion 2 of 4
Why name the files in git add instead of always using git add .?
Question 3 of 4
Which of these commit messages will help you a month from now?
Question 4 of 4
A saved version was wrong. Which command undoes it without erasing the history?
Choose an option. The explanation appears after your attempt.