Stop 5 of 6
Build & preview: one checked step at a time
Your first tasks built, step by step, with a working Preview link you can open and try.
1–2 sessionsMilestone · Your first Preview
What your agent will do
- A1Works on a branch, one small task at a time, with a checkpoint (commit) after each working step.
- A2Runs the app on your computer and shows you each result.
- A3Pushes, opens a pull request, runs the checks (lint, type check, tests) and shares the Preview link.
What you do
- Try each result in the browser and say what you'd change.
- Open the Preview link on your phone too.
- When something breaks, say what you did, what you expected and what happened.
- Try each result in the browser and say what you'd change.
- Open the Preview link on your phone too.
- When something breaks, say what you did, what you expected and what happened.
When something breaks: the debugging loop
Errors are normal. Your agent follows four steps, never guessing:
- 1ReproduceMake the problem happen again, on purpose.
- 2FindRead the error and the logs; narrow down where it breaks.
- 3FixFix the root cause, one change at a time. No guessing.
- 4ProveAdd a test that would have caught it, and try it end to end.
Report a problem to your agent →Where to look when something breaks →
The ideas behind it
When something goes wrong
“Port 3000 is already in use”Another copy of your app is running. Close it or ask your agent to stop it. More help →
The app shows a blank or error pageYour agent reads the browser console and the terminal to find why. More help →
The Vercel build failedYour agent reads the build logs, fixes the cause and pushes again. More help →
Quick check · 1 question
Your app broke after a change. What's the safest first step?
Copy for your agent
We're at the Build stage. Read SPEC.md and tasks/todo.md, tell me which task is next, build it on a branch, and show me the result before moving on.
Saved on this device only. No account needed.
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