Have Claude or ChatGPT write the test, then write code until it passes — TDD made painless.
7 min · Reviewed 2026
The big idea
Writing tests first feels slow until AI does it for you. Ask Claude for the test, then write the code that turns it green — your function gets defined by what it should do, not what was easy to type.
Some examples
You ask ChatGPT 'write a Jest test for a function that converts kebab-case to camelCase' and start with a failing test.
Claude writes Vitest cases including the empty string and double-dash edge cases before you write a single line of the function.
Cursor sees your test file and offers to scaffold the function signature that would satisfy it.
Copilot Chat suggests two extra tests you didn't think of when you ask 'what edge cases am I missing?'
Try it!
Pick the next utility you need to write. Ask AI for three Jest or Vitest cases first, run them red, then write the function.
End-of-lesson check
15 questions · take it digitally for instant feedback at tendril.neural-forge.io/learn/quiz/end-builders-aicoding-ai-test-first-r9a8-teen
What is the core idea behind "Asking AI for the Test Before the Function"?
Have Claude or ChatGPT write the test, then write code until it passes — TDD made painless.
Ask AI to optimize a slow query you're already running.
Consider contributing back to an open-source tool you used in the build
seed data
Which term best describes a foundational idea in "Asking AI for the Test Before the Function"?
unit test
TDD
red-green
Jest
A learner studying Asking AI for the Test Before the Function would need to understand which concept?
TDD
red-green
unit test
Jest
Which of these is directly relevant to Asking AI for the Test Before the Function?
TDD
unit test
Jest
red-green
Which of the following is a key point about Asking AI for the Test Before the Function?
You ask ChatGPT 'write a Jest test for a function that converts kebab-case to camelCase' and start w…
Claude writes Vitest cases including the empty string and double-dash edge cases before you write a …
Cursor sees your test file and offers to scaffold the function signature that would satisfy it.
Copilot Chat suggests two extra tests you didn't think of when you ask 'what edge cases am I missing…
Which of these does NOT belong in a discussion of Asking AI for the Test Before the Function?
You ask ChatGPT 'write a Jest test for a function that converts kebab-case to camelCase' and start w…
Claude writes Vitest cases including the empty string and double-dash edge cases before you write a …
Cursor sees your test file and offers to scaffold the function signature that would satisfy it.
Ask AI to optimize a slow query you're already running.
What is the key insight about "The rule" in the context of Asking AI for the Test Before the Function?
Ask AI to optimize a slow query you're already running.
Consider contributing back to an open-source tool you used in the build
Tests first, code second — let the AI handle the boilerplate so the order finally feels natural.
seed data
What is the recommended tip about "Review before you run" in the context of Asking AI for the Test Before the Function?
Ask AI to optimize a slow query you're already running.
Consider contributing back to an open-source tool you used in the build
seed data
AI code is a first draft. Read through it, understand each line, and test on sample inputs before merging into real proj…
Which statement accurately describes an aspect of Asking AI for the Test Before the Function?
Writing tests first feels slow until AI does it for you. Ask Claude for the test, then write the code that turns it green — your function ge…
Ask AI to optimize a slow query you're already running.
Consider contributing back to an open-source tool you used in the build
seed data
What does working with Asking AI for the Test Before the Function typically involve?
Ask AI to optimize a slow query you're already running.
Pick the next utility you need to write. Ask AI for three Jest or Vitest cases first, run them red, then write the function.
Consider contributing back to an open-source tool you used in the build
seed data
Which best describes the scope of "Asking AI for the Test Before the Function"?
It is unrelated to ai-coding workflows
It applies only to the opposite beginner tier
It focuses on Have Claude or ChatGPT write the test, then write code until it passes — TDD made painless.
It was deprecated in 2024 and no longer relevant
Which section heading best belongs in a lesson about Asking AI for the Test Before the Function?
Ask AI to optimize a slow query you're already running.
Consider contributing back to an open-source tool you used in the build
seed data
Some examples
Which section heading best belongs in a lesson about Asking AI for the Test Before the Function?
Try it!
Ask AI to optimize a slow query you're already running.
Consider contributing back to an open-source tool you used in the build
seed data
Which of the following is a concept covered in Asking AI for the Test Before the Function?
unit test
TDD
red-green
Jest
Which of the following is a concept covered in Asking AI for the Test Before the Function?