Do we need at.js on the NodeSDK implemenation?

[Pravinrams1]

I am new to Adobe Target SSR implementation. We have used CSR global mbox before and now our new site is built on React so would like to take advantage of Server Side Rendering and I am using NodeSDK. Is at.js necessary for SSR implementation? I am loading at.js in the header but just really want to know if that is necessary for nodesdk. Also, the documentations for getoffer and applyoffer is vague and confusing.

Also, I see lot of "undefined" values in my request (Screenshot below), is it a problem?

Can someone help me with some details, please?

Thanks

Praveen