Running on your computer
The app shows a blank or error page on your computer
- What you see
localhost:3000is empty, white, or shows an error overlay.- Why it happens
- Something broke while building or running the page. The details are in the browser console and in the terminal.
- How to fix it
- Copy the error text from the page or the terminal (remove any key first).
- Give it to your agent with the report format: what you did, expected and got.
- If it worked a moment ago, ask to go back to the last version that worked.
Message for your agent
My app shows a blank page at localhost:3000. Read the terminal and the browser console, find the root cause, fix it, and add a test so it can't come back.
Tip
How to prevent it: Small steps with a checkpoint after each make these easy to undo.
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