The ability to launch 8th Wall apps from direct URLs is available with Plus, Pro, and Enterprise plans. The Starter plan does not support direct URL access, so all users are first re-directed to the Featured Project page on 8thwall.com and must click the “Launch” button to begin.
A detailed table comparing features by plan can be found here: 8th Wall | Pricing and Plans - WebAR, AR, WebVR Developer Tools and SDK
To upgrade to a higher plan, please follow the instructions at https://www.8thwall.com/docs/guides/account-settings/#change-plan