This tool gives approx award availability for CX flights ONLY (i.e. no codeshare/partner flights). It uses the unauthenticated query API (e.g. when you browse reward flights on Cathay website without logging in).
The main benefit is to quickly explore availability across different routes, classes & dates when planning a flexible getaway.
It also gies you the value of Asia Miles (e.g. HK$ per mile) based on redemption across different routes, classes & dates (correctly accounting for Airfare only; NOT TAX!)