What "building with AI" really means
You do not need to code. You need a clear one-page idea.
The idea
Today you can describe a small tool in plain words and an AI will write the code. People call this vibe coding. It works well for small, simple tools: a calculator, a checklist, a form, a Sheets helper.
It works only when you are clear about three things: who uses it, what goes in and what comes out. This is a spec. A one-page spec is the most valuable thing you can write.
AI-written code can have bugs and security gaps. Start with tools that do not store private data. Test with simple numbers you can check by hand.
Your task
Write a one-page spec for a small tool
Idea: a bill splitter for friends. You will use this spec in the next lessons as a model.
Help me write a one-page spec for a small web tool called "Bill Splitter". The tool: friends enter the total bill, the number of people and a tip percent. It shows the amount each person pays. Write the spec with these headings: Who uses it, Inputs, Output, 3 test cases with exact numbers, What it must NOT do. Rules: Work out the test case answers carefully. Keep the whole spec under 150 words. The tool must not store or send any data.
What you should get
A real example of a good result. Your wording will differ a little. The shape and the facts should match.
Printed resultExample
Who uses it: Friends splitting a restaurant bill on a phone. Inputs: Total bill (Rs), number of people, tip percent. Output: Amount each person pays, rounded to the nearest rupee. Test cases: 1. Rs 2,000, 4 people, 10% tip: each pays Rs 550. 2. Rs 1,200, 3 people, 0% tip: each pays Rs 400. 3. Rs 900, 2 people, 5% tip: each pays Rs 473 (472.5 rounded). Must NOT: store data, send data anywhere, ask for names or phone numbers.
Check yourself
Finished?
Stamp this ticket. Your pass on the home page gets punched.