Calling /login Endpoint Directly Results in Error "Missing client parameter"

Last Updated: Feb 20, 2026

Overview

This article details an issue where users see an increase in the number of failed login attempts with a description message "missing client parameter" and the log message is not clear.

Cause

This error occurs when the `client` is missing when visiting `/login`.

Solution

This can occur if users are hitting `/login` directly rather than going through `/authorize`. To avoid this, ensure that applications are only initiating logins via `/authorize`.

In the case where users may visit `/login` themselves, this can be solved by configuring a default login route. For more information, refer to Configure Default Login Routes.