Hello @AlexTrovato !
I bought a Zigbee air quality sensor (Smart Air Housekeeper), to monitor the air quality at my place because in Bangkok it’s not great right now 
On the Zigbee2mqtt side, everything is recognized :
The JSON state sent :
Now, in Gladys I don’t have PM2.5 or formaldehyde for now :
What would be the steps to properly add that to the Zigbee2mqtt integration?
I can do it myself but I wanted your feedback 
It’s not very complicated, but you need to know it.
First, you must be sure that the category/the type exists in Gladys.
It’s recommended to start from your device page Tuya TS0601_smart_air_house_keeper control via MQTT | Zigbee2MQTT, then look at the details of the « expose » for your feature (we don’t handle options):
Here, you can see that your feature is of type « numeric », that the name of its attribute is formaldehyd, and you even have its unit µg/m³.
On the zigbee2mqtt service side, features are split by value type (see files in the folder server/services/zigbee2mqtt/exposes):
Then, in each of these files, you have different attributes in a « complex » object:
In your case, it’s the « names » attribute that matters.
In it, you’ll find sub-objects, organized as follows:
The read_only and has_feedback information is determined from the access attribute of the expose.
The min / max, unit information is determined from the attributes of the same name in the expose.
The units can be generic; add them in this file server/services/zigbee2mqtt/utils/features/mapUnit.js.
Any override added for the mapping of your feature can be forced by adding the attribute forceOverride: true to the defined feature (see linkquality in the numeric file). With this option, the attributes calculated « generically » will be overridden if they are defined in your mapping.
I think you have all the information to add a « basic » feature mapping.
For complex cases (enum or composite), there will be more detailed explanations.
Let me know if you manage with this @pierre-gilles
It’s beautifully explained
That’s very clear @AlexTrovato, thanks for taking the time
I think this message could be kept somewhere in case we have developers who want to help us integrate more Zigbee devices!
@pierre-gilles
Making a short tutorial would be great because it’s true that this is the missing/frustrating part when trying to see if we can help — we don’t necessarily have the time to comb through the whole forum to gather bits of the necessary information, whereas those who have the required knowledge can, at low cost and in less time, share it through a tutorial and that then multiplies the development possibilities for others! Knowledge is only valuable when it’s shared 
2 messages were split into a new topic: Is my inverter compatible with Zigbee2mqtt?
