i configured rest sensors that query the tado api v2. the mobile/1.9 api does not seem to support zones. this still doesn't solve the problem of displaying the set and the actual temperatur together, put i lets home assistant gather all tado data from all zones — and lets me push and view them in grafana.

(replace HOME_ID, USERNAME and PASSWORD with your own values and query all avalailable zones.)

sensor:
- platform: rest
  resource: https://my.tado.com/api/v2/homes/HOME_ID/zones/1/state?username=USERNAME&password=PASSWORD
  value_template: '{{ value_json.sensorDataPoints.humidity.percentage }}'
  unit_of_measurement: °C
  name: 'tado zone 1 humidity'
- platform: rest
  resource: https://my.tado.com/api/v2/homes/HOME_ID/zones/1/state?username=USERNAME&password=PASSWORD
  value_template: '{{ value_json.sensorDataPoints.insideTemperature.celsius }}'
  unit_of_measurement: °C
  name: 'tado zone 1 temperature'
- platform: rest
  resource: https://my.tado.com/api/v2/homes/HOME_ID/zones/1/state?username=USERNAME&password=PASSWORD
  value_template: '{{ value_json.setting.temperature.celsius }}'
  unit_of_measurement: °C
  name: 'tado zone 1 set temperature'
- platform: rest
  resource: https://my.tado.com/api/v2/homes/HOME_ID/zones/1/state?username=USERNAME&password=PASSWORD
  value_template: '{{ value_json.activityDataPoints.heatingPower.percentage }}'
  unit_of_measurement: '%'
  name: 'tado zone 1 heating power'

i particularly like the heatingPower.percentage which lets me observe how the thermostats request heating power from the boiler.

tado values in grafana

btw., there should be ways also to set the temperature manually, like stephen c phillips pointed out here. it actually works, if you send a PUT request to

https://my.tado.com/api/v2/homes/HOME/zones/1/overlay?username=USERNAME&password=PASSWORD

with a payload like

{setting: {type: "HEATING", power: "ON", temperature: {celsius: 22}}, termination: {type: "MANUAL"}}

even if the tado api is not official or public yet, with this data it should actually be possible to build a custum component, possibly by fiddling with the generic thermostat component.