/api/auth/setup returns 401 Unauthorized after deploying (Kinde Next.js SDK)

/api/auth/setup returns 401 Unauthorized after deploying (Kinde Next.js SDK)

What's going on

The /api/auth/setup route in @kinde-oss/kinde-auth-nextjs returned 401 Unauthorized after deployment, while everything worked locally. The setup endpoint rejected the request in the production environment with no useful error beyond the 401. Local dev and production behaved differently, which pointed at the SDK's setup flow rather than the app's configuration.

The verified fix

Fixed upstream in PR #268 (the setup flow handling); upgrade @kinde-oss/kinde-auth-nextjs to a release from February 2025 or later containing that fix. The maintainers confirmed the fix in the thread after discussing the deploy-vs-local difference internally. If the 401 persists on a current SDK version, double-check that the deployed environment serves the same auth routes as local, since a missing route produces the same symptom. Source: https://github.com/kinde-oss/kinde-auth-nextjs/issues/170

How to use this

Take the question above and check if it matches what you're seeing. If it does, work through the verified fix step by step. Start with the cause described first, because that's what tells you the fix applies to your setup, then apply the changes in the order given. Verify by re-running whatever failed before, and expect the same behavior the thread author reported.

Someone asked: The /api/auth/setup route in @kinde-oss/kinde-auth-nextjs returned 401 Unauthorized after deployment, while everything worked locally. The setup endpoint rejected the request in the production environment with no useful error beyond the 401. Local dev and production behaved differently, which pointed at the SDK's setup flow rather than the app's configuration. The verified answer: Fixed upstream in PR #268 (the setup flow handling); upgrade @kinde-oss/kinde-auth-nextjs to a release from February 2025 or later containing that fix. The maintainers confirmed the fix in the thread after discussing the deploy-vs-local difference internally. If the 401 persists on a current SDK version, double-check that the deployed environment serves the same auth routes as local, since a missing route produces the same symptom. Source: https://github.com/kinde-oss/kinde-auth-nextjs/issues/170 Discussion and confirmation live at https://vectle.com/threads/thr5qHnip03dtNzvj9H75pIQ