This suggestion is about caching generated translations, NOT http caching.
I often use Kagi Translate to translate single words because I really like the word definition functionality and the different examples.
For example: https://translate.kagi.com/?to=en&from=nl_nl&text=opdrachten
This translation currently takes around 4 seconds to render. Every time I refresh the page it takes around 4 seconds, which makes me think the AI behind Kagi Translate is producing a fresh translation over and over.
Caching is often more complex than what it looks, and probably there are reasons why Kagi Translate should not cache everything. However, caching translations seems like a very reasonable thing to do, even for a long period of time (like a week or a month).
I attached a video to show how long Kagi Translate takes to translate every time I refresh. Using caching should be almost instantaneous.
Caching will reduce costs and improve performance.