Fight enshittification. For whatever reason, many travel sites no longer send full details in the e-mail confirmation, they want you to click through to the site...which means I can't forward it to plans@tripit.com for automatic import.

Immediately after booking something,I tell Gemini to add it to my TripIt. Works great. I have a little prompt explaining how I like it formatted that I cut and paste, so I can just make this a one-click prompt. I could also have it add flights to my.flightradar24.com.

I also use Gemini in Chrome to add appointment confirmations to my calendar. Or remember things in Google Keep.

There's lot of use cases for this kind of thing.