Terminal

You might say

AI gave me a command to run, but I don't know what it will do. Is it safe to run?

Run text commands in a specific folder on your computer or serverA terminal gives you a prompt where commands can start tools, install packages, inspect files, and run a project. The current directory changes what a command affects. Read the command and confirm the path before running anything that changes or deletes files.

zsh — my-first-page

$ npm run dev > my-first-page@0.1.0 dev ✓ Ready in 1.2s → Local: http://localhost:3000 Open this address in your browser and you will be able to see your page

You can say this to an AI Agent

Explain what each command will do and confirm that the terminal is in the project directory containing package.json. Run commands one at a time, stop on failure, keep the command and first error, and do not add sudo automatically.

When to use it

Start a development server
$ npm run dev✓ Ready in 1.2s→ http://localhost:3000
Install project dependencies
$ ls List the contents of the current directoryindex.html my-first-page$ cd my-first-page Enter the project directory
Run build and test commands
▲ Build failedError: Cannot find module 'react'at build (build.js:12)
Inspect files, processes, and logs
$ npm installadded 42 packages in 6s$ npm run build✓ built in 3.2s

When NOT to use it

Paste a command you do not understand with elevated permission
Error: …Error: …(multiple error messages)
✕
Run project commands from an unrelated directory
~/Desktop $ npm run devnpm error: no package.json
Share terminal output that contains secrets
Pasting several commands at once…npm installError: network timeoutIt becomes hard to tell which command caused later results.
Use a destructive command with an unverified path or wildcard
$ sudo rm -rf …Run with elevated privileges

Anatomy

$ npm run dev ✓ Ready in 1.2s → http://localhost:3000

Starting with $ or %; the preceding path represents the current working directory

The first word specifies an external program or shell built-in function, such as npm, cd, ls, git

Supplementary information after the command, such as run dev specifies the script to be executed

Results, warnings, and errors returned by commands; first look for clues that lead to action

Variants

cd & ls

cd my-first-page ls

Go into the project directory and list the files in it

npm run

npm run dev

Execute startup or build scripts declared in package.json

Ctrl+C

Ctrl + C

Stop a command or development service running in the foreground

clear

Clear the display when there is too much content on the screen

Typical use cases

Run a project

zsh — my-first-page

$ npm run dev > my-first-page@0.1.0 dev > vite ✓ Ready in 1.2s → Local: http://localhost:3000 The development service runs in this process; the local address will stop responding after aborting the process

Install packages

zsh — my-first-page

Failed to compile Error: Cannot find module 'react' at build (vite.config.js:12) at processTicksAndRejections (node:internal) ↑ The error message and call stack must be judged together with the execution command

Build and test

zsh

~/Desktop $ ls Documents Downloads my-first-page ~/Desktop $ cd my-first-page ~/Desktop/my-first-page $ ls index.html package.json README.md

Read logs

zsh — my-first-page

✓ Ready — http://localhost:3000 ^C ~/Desktop/my-first-page $ The service has stopped and the terminal returns the prompt Ctrl + C: Abort the command running in the foreground

Recommended tool

Web fine-tuning tool · Selector Pro

Select page elements for precise AI edits

Click a button, text, or card, note the change, then copy its exact location to AI.

Open Selector Pro website

An Agent asks you to run npm install and npm run dev, but the terminal just opened and you do not know the current directory. What comes first?

A. Add sudo to both commands before any permission error appearsB. Paste both commands at once and locate the project only after an errorC. Use pwd and ls to confirm the project, then run each command and read its output