Simulation-measured completeness of AGN in the single-band detected catalogue as a function of the 0.5–2 keV input flux (erg cm² s^–1) in differential (upper panel) and cumulative manners. The solid and dashed blue lines indicate the detected AGN with DET_LIKE > 6 and DET_LIKE > 5, respectively. For comparison, we also plot the sky coverage area curve measured by ersensmap adopting DET_LIKE ≥ 5 normalised to a total area of 1 (black line).