Tutorials · Chapter B (2/4) · ~10 min
AI for coding
Try it → see it → read → next
Use AI to explain, debug, and test — never to merge unreviewed code.
Try tools: Code & developers
Try yourself
Playground
AI coding assistant patterns
Same snippet — three safe workflows: explain, debug, test.
function total(items) {
let sum = 0
for (let i = 0; i <= items.length; i++) {
sum += items[i]
}
return sum
}PromptExplain this function line-by-line for a beginner. No rewrites yet.
Recap
What you just did
You ran three playbooks on the same snippet: explain, find bug, write tests — the safe daily rhythm.
Teach
How it works
1) Explain before you change
Explain this code line-by-line. Assume I know basic JavaScript.
Do not rewrite yet.
[paste]
2) Debug with a narrow ask
Find the bug causing wrong totals. Show a minimal diff only.
[paste + error message]
3) Tests before refactor
Write 3 unit tests for edge cases. Then suggest one refactor if tests pass.
[paste]
Always run tests locally. Never paste secrets, API keys, or customer data.
Use it
When you'd use this
- Learning unfamiliar codebases
- Stuck on an error message
- Drafting tests or docstrings
Watch out
Watch out
- AI invents APIs — verify against docs
- “Fix everything” diffs can break behavior
- Don't commit code you didn't read
Try next
Try this next
Use the How to use AI for code review recipe on the reference shelf.