v0 preview connects but the published integration fails

1. Inspect the v0 project settings.

   Open the project settings and inspect Environment Variables. Compare the names required by the generated integration with the configured names. Also inspect Integrations to confirm which service the project is intended to use.

2. Follow the connected Vercel project.

   In v0’s project settings, locate Vercel Project and open that connected project. Compare it with the project serving your public app. Record a mismatch instead of adding variables to a different project with a similar name.

3. Check the production build.

   In Vercel, open Deployments, choose the failing production deployment and expand Building. Read its build log and note its revision. Then open Settings, Environment Variables and verify the required names are available for Production.

4. Retest after a new deployment.

   Save any corrected production configuration and create a fresh deployment. Open its URL and run the failing integration once. If the build succeeds but the action fails, use the action’s response and server log to locate the runtime failure.

WORKSThe connected production project completes the integration with its intended settings.

BROKENThe v0-to-Vercel project mapping or production configuration leaves the call unable to run.

Ranked in the order to investigate, not by claimed frequency.

1. The settings were changed in a different project.

   Apply the integration configuration to the connected project that actually serves the app. Keep a clear association between the v0 project, Vercel deployment and live domain before making further changes.

2. A preview value has no production equivalent.

   Set the correct production credential or public endpoint for the integration. Do not assume a working preview’s service account is suitable for real users, and keep secret values out of frontend code.

3. The published build was created before the configuration change.

   Create a new build after the settings are saved. Verify that production serves that deployment and re-run the integration action, not just the homepage.

• An integration can supply configuration, but its presence is not evidence that the generated code uses the intended names. Compare the code’s environment reads directly.
• If the project is exported and hosted elsewhere, that host’s configuration is authoritative for its deployment. Use the base environment guide instead of assuming v0 settings configure an unrelated host.

When to stop and hand it over

Hand it over if the connected project, Production scope and new deployment agree but the service call still fails. Provide the non-secret variable names, linked project and first relevant failure. Ask for the generated integration code to be checked against that configuration.