You can choose a name for your Nest device when you first get the device. Other than that, if you ask Alexa to change the temperature without specifying an amount, she will change the temperature by 2°F or 1°C.
Nest Thermostat
“Alexa, what’s the temperature in {thermostat name}?”
“Alexa, what’s the temperature in the house?”
“Alexa, what’s the temperature in the {room}”. Example: “Alexa, what’s the temperature in the bedroom”
“Alexa, what temperature is my {thermostat name} set to?”
“Alexa, set the {thermostat name} temperature to {number} degrees”. Example: “Alexa, set the {thermostat name} temperature to 30 degrees”
“Alexa, change the {thermostat name} to {number} degrees”. Example: “Alexa, change the {thermostat name} to 21 degrees”
“Alexa, turn my {thermostat name} temperature to {number} degree”. Example: “Alexa, turn my {thermostat name} temperature to 24 degree”
“Alexa, decrease the {thermostat name} temperature”
“Alexa, increase the {thermostat name} by {number} degrees”. Example: “Alexa, increase the {thermostat name} by 5 degrees”
“Alexa, make my {thermostat name} warmer by {number} degrees”. Example: “Alexa, make my {thermostat name} warmer by 5 degrees”
Nest Camera
“Alexa, show the {camera name}”
“Alexa, show feed from the {camera name}”
“Alexa, show {camera name} feed”
“Alexa, hide the {camera name}”
“Alexa, hide feed from the {camera name}”
“Alexa, hide the {camera name} feed”