The terminal surface - Copilot CLI

This is the shortest lesson in the chapter on purpose. There is one more surface to name and then close the book on: the Copilot CLI, a terminal-native way to reach the same assistant.

It is, deliberately, a small part of this course: the course is IDE-first, and nothing about the CLI changes that. But it exists, and it is worth a page so you are not surprised when a colleague mentions it.

The thing to understand is that it is the same Copilot, not a separate tool to learn. Same GitHub account, same Copilot plan, and - the part that matters for everything you built - it reads the same rules files: the AGENTS.md at the root of your repos applies in the terminal as it does elsewhere (per this course’s September 2026 verification; the Copilot docs’ CLI section covers installing it and adding its custom instructions). No second copy of your conventions to maintain - the CLI inherits that work. The CLI became generally available in early 2026 (per this course’s September 2026 verification).

So when would you reach for it? When you are already in the terminal and moving would be friction. You are in a shell mid-flow on a git operation or a quick check inside the service, and you want to ask the agent something without switching windows to the editor. That is the niche: terminal-native moments, not a primary workspace. For the careful, multi-file, review-heavy work this course is built around, you still want the editor, where the full review machinery lives.

That’s the whole footnote. Don’t overbuild a CLI habit; treat it as the same assistant answering the door when you happen to already be standing in the terminal.

And that closes the surfaces. You have now seen Copilot as the same assistant across VS Code, JetBrains, and the terminal - one account, one set of conventions, three places to stand. Everything left is putting it together into a working rhythm. Next chapter: the daily workflow.