Preview and Production

The Vercel build failed

What you see
The Preview or deployment shows “Build failed” or “Error”.
Why it happens
Vercel couldn't turn your code into a site: often a type error, a lint error or a missing environment variable.
How to fix it
  1. Ask your agent to read the build logs with the Vercel CLI.
  2. It explains the cause, fixes it, runs the checks locally and pushes again.

Message for your agent

My Vercel build failed. Read the build logs, explain the cause in one sentence, fix it, run lint, type check and tests locally, then push again.

Tip

How to prevent it: Run lint, type check and tests before every push.

Still stuck?Report it to your agent, clearly

Hands-on test on Mac and Windows pending · Last reviewed Nov 8, 2026