Write the one-page spec

Build-along · ~20 min at your own keyboard

AI builds what you describe. If you describe it badly, it builds the wrong thing fast. A one-page spec fixes that. It has six parts. Who uses it. The one job it does. The data it holds, as a list of fields. What 'done' looks like, so you can tell when to stop. What it must never do. And the smallest version that is still useful. The smallest version is the hard part. Most first builds fail because they try to do five jobs. Pick one. You can add the rest after the first one works. This page is also what you paste into the builder in the next lesson.

Ladder · Level 5The long version: Building with AI ↗

Your starter: One-page spec

Template

Make it yours: Fill every section for one tool you would use this month. If a line could describe anyone's tool, make it about yours.

SPEC: [tool name] for [your business]

USERS (named people or roles, and the device each one uses)
-

THE ONE JOB (one sentence, no "and")
When someone opens it, they can

DATA (ten fields or fewer: name, type, mark private ones)
- [field] (text, number, date, or a choice from a list) [private?]

DONE WHEN (three checks you can test with a clock, a count or a yes/no)
1.
2.
3.

NEVER (at least two)
-
-

SMALLEST VERSION (three lines or fewer)

LATER (good ideas that are not version 1)
-

The coach checks that what you paste back is your own work. The starter pasted back unchanged won't pass.

Do this

0/7

Checkpoints

▸You should now see a one-page spec with six labeled parts.
▸You should now see a field list with a type next to each field.
▸You should now see three done checks you can test, and a smallest version of three lines or fewer.

The three ways this goes wrong

The ONE job sentence has 'and' in it, or the spec runs to three pages. — Pick the half you do most often. Move the other half to a 'Later' list at the bottom. A spec that fits one page is a spec you can finish.
The done checks say 'it works well' or 'it looks good'. — Rewrite each as something you can test with a clock or a count: 'adds a job in under 30 seconds', 'shows all open jobs on one screen'.
You listed 25 fields. — Keep the fields you use every day. Cut the rest. You can add a field later in about a minute. Removing a field from live data is harder.

Share what happened

Paste your one-page spec with all six parts: users, the one job, the data fields, done checks, never-do list, and smallest version.

Strip API keys, passwords, and tokens before you paste. Swap them for [KEY].

🔒 Don't paste confidential, personal-health, or payment info.