Just so you know:
If a device uses only the standard Zigbee clusters, then typically all a developer needs to do to make it work with an existing Edge Driver for a device that uses those same clusters is to add its fingerprint to that Edge Driver.
However, the Zigbee standard allows device manufacturers to use their own unique clusters, and they are not required to publish those details. This is called “manufacturer proprietary” code. Devices using proprietary clusters can still be added to another company’s hub, but they may just not work, even for something as simple as reporting temperature.
Figuring out exactly what messages are being sent using those proprietary clusters is a timeconsuming and challenging task, and almost always requires actually having the physical device to work with.
TUYA USES A LOT OF UNIQUE CODE FOR ITS DEVICES
Tuya products use a LOT of manufacturer-proprietary code. Their devices can still be certified as “Zigbee 3.0” even though they are using nonstandard clusters. Tuya themselves acknowledge this without going into detail:
https://support.tuya.com/en/help/_detail/K9f3zl7ur8l5f
Anytime you see the cluster EF00 , that is a manufacturer-proprietary cluster that Tuya uses, and pretty much guarantees it is going to require custom code to work with any other platform.
The really tricky part is that unlike standard Zigbee clusters, which have the same format every time, Tuya appears to use the EF00 cluster as what developers call a “tunnel” to carry different information for different devices, making it very difficult to reverse-engineer without an actual device. And not easy even then.
So if you buy a Tuya device, even one certified for Zigbee 3.0, understand that using it with SmartThings may require a significant amount of custom work, not just adding the fingerprint to an existing Edge Driver.
It doesn’t mean it’s impossible, but it isn’t easy, either.
MATTER MIGHT MAKE THIS EASIER
There is a glimmer of hope. Tuya has said that it is intending to support the Matter standard. It is possible (but not guaranteed) that sometime next year customers will be able to buy a specific Tuya hub model, add their Tuya devices to that, then add that hub to their SmartThings account and it will bring some of its devices with it without requiring any custom code. But not all models and probably not all features. Still, it should be an easier method than what we have today. But that’s in the future, and only a possibility, not a certainty.
OPTIONS FOR TODAY
For now, do feel free to continue to post requests for custom Edge Drivers for Tuya devices using custom clusters, including the EF00 cluster.
Just be aware of the fact that if one does not already exist, creating a compatible Edge Driver for a device using a nonstandard cluster like EF00 will be a much more difficult task than for a more standard device, and isn’t always one that community developers have the time for. 
