Prius in for an oil change

I've only been a professional wrench for +40 years with multiple licenses and I've seen and heard this all before. You asked, but the decisions are all yours. Wish you the best.

 

Again,,,, You should never 'add brake fluid'. You're just making a problem if you do. There is a Max and Min line for a reason.
It's a translucent reservoir for a reason.
Resist the urge to open that cap and let moisture in.

 

Most if not all of Toyota’s service recommendations are miles or months, whichever comes first.

Concur about not adding brake fluid, it typically drops as a consequence of pad wear, and it’s pointless to “top up”. However, regarding the cap on brake fluid reserve, while a snug fit, don’t see it as being air-tight, sealed.