GitHub Copilot tutorial: setup, strengths, costs, mistakes, prompts

Turn it on

Sign in to github.com, open Copilot settings and pick a plan: Free ($0), Pro ($10/mo), Pro+ ($39/mo), Max ($100/mo) per GitHub.

Install in your editor

Install the GitHub Copilot extension in VS Code, JetBrains or Visual Studio and sign in with the same GitHub account.

Settings worth changing

In GitHub Copilot settings, review whether suggestions matching public code are allowed, and set a budget for extra usage so it can't run past what you decided.

Good at

• Inline completions while typing
• Explaining unfamiliar code in your repo
• Writing tests for a function you select
• Agent tasks on an issue that produce a pull request to review

Careful with

• Plausible code that calls functions that don't exist: run it
• Old library versions: tell it your versions
• Agent PRs: review every diff before merging

How it charges

Every plan includes a monthly allowance of AI credits, 1 credit = $0.01; chat and agents use credits; after that you can set a budget (GitHub).

Cheaper habits

• Use inline completions for small edits instead of agent runs
• Give agents one well-scoped issue, not "fix everything"
• Set the budget to $0 if you never want overage

Merging without tests

Fix: require CI to pass on Copilot PRs.

Secrets in prompts

Never paste API keys into chat; use environment variables.

Test writing

Bad: "write tests"

Good: "Write pytest tests for parse_invoice() in invoices.py: happy path, missing total, negative amount, and a date in DD/MM format. Don't change the function."

Why: named function, named cases, and a boundary.

GitHub lists Free ($0), Pro ($10/month), Pro+ ($39/month) and Max ($100/month). Every plan includes a monthly allowance of AI credits, where 1 credit = $0.01. You use credits when you chat with Copilot and work with agents. When credits run out, you can set a budget for more usage.

Steps: 1) Pick a plan on GitHub. 2) Install the Copilot extension in your editor. 3) Ask in chat, then review every change before you accept it.

Source: https://github.com/features/copilot/plans. Checked Oct 28, 2026 against the official pages linked here. Plans change, so confirm on the official page before you pay.