officially we have a rain sensor, except that the electronics is disabled
Per the manual (p. 291), the puck next to the rear-view mirror that looks like a rain sensor is a temperature and humidity sensor used to detect fog on the windshield. I don't believe it's disabled - at the very least, I've had the car automatically turn on the front defog in appropriate situations several times. The same puck is also present on other Toyota cars I've driven that have automatic climate control systems but nevertheless don't have automatic, rain-sensing wipers.