I read
https://developers.google.com/glass/develop/gdk/quick-start
We recommend installing the ADT package to simplify development. The rest of these steps assume that you installed it. Click Window> Android SDK Manager. Install the Sneak Peek SDK and Google GDK platform for Android 4.0.3 (API 15). Everything else is optional.
but in my Sdk kernel I canβt find it, I also update my Sdk box, but also did not find it. 
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