This folder is for database of agent file system data that gets uploaded from them, and if you have the option to automatically retrieve system data upon agent registration, it will perform that action. Otherwise the data can also be manually requested.
This option very often causes disk space issue on the Manager as it collect a large amount of data.
To check this option it’s under the 'Admin' tab, then 'Settings'. Then in the middle you should notice an 'Agent Settings' tab. There should be a checkbox named 'Enable file system data retrieval at agent registration'
If this is enabled, then this data is collected upon registration.
The created files in this folder can safely be deleted. See the cause section of you want to disable this option in future