Huh. From the name I thought it would be something to remove context (in the same way a "de-icer" removes ice) perhaps to remove bias. Instead, this is a system to add context to sentence so that it can be understood in isolation.

I had similar doubts initially. I went for the name they used in the paper: https://arxiv.org/pdf/2102.05169.pdf. It takes the sentence out of its original context. A "contextualizer" might instead turn a transcluded paragraph included as is in different notes and integrate it more coherently in the context.

this is pretty cool