The Rarity of the Module.
This value is restricted to the rarity types of Modules. (As of time of writing, all systems have the same rarities, but it's possible new rarities will be introduced for special Modules/Weapons/Descendants/etc. - That's why this isn't a common universal property.)
Text Transcendent Ultimate Rare Normal
{ "type": "PROPERTY_CONSTRAINT_SCHEMA", "constraints": { "type_constraint": "_txt", "allowed_values": [ "Transcendent", "Ultimate", "Rare", "Normal" ] } }