Openweathermap configuration

There seems to be a missing value in the HACS addon Weather-Card. See below screenshot:

The weather data provider I’m using is OpenWeatherMap. In my configuration I have the below respective settings:

  - platform: openweathermap
    api_key: xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    mode: freedaily

In the OpenWeatherMap documentation, it says I can alternatively use the OpenWeatherMap “sensor” instead of the OpenWeathermap “platform”. Currently, I only have the platform defined (shown above). Do I need to use the sensor instead of the Platform; or, do I need to specify both sensor and platform in my configuration?

Thanks in advance!