[Solved] Devices tags creation

I’m looking for help to understand how add tags to a specific device .
Despite having read the Losant Doc. I cannot realize how do that.
Also I saw the Losant University example about context variables, but I do not understand
from where the tags used on that example comer from.
Thanks

Here is our documentation on device tags. In short, tags are key/value pairs used primarily for device categorization so that similar devices can be grouped together in your device queries.

You can also use device tags to store meta information about Losant devices; for example, a number of people store third-party IDs that correlate to other services (such as Particle or Sigfox) and then use those values in Get Device Nodes in workflows to interact with those devices.

Similarly tags are being used for device specific event thresholds, etc. Various static configuration settings. I’ve mentally got this down to attributes are for time series reporting of device state, the rest (configuration etc) goes into the tags.

@Dylan_Schuster @WoobaGooba

I understand what you are explaining me.
My point is how you create a device tag. Which is the way to do that?
I need to understand that in order to implement what Brandon suggested me to do for compare payload data with current slider value.
Thanks

Looks like this was elaborated here: