Two scouting modes
Normal scouting is sent as Attack with spies only. It is visible immediately and the defender receives a report. Covert espionage moves at 50% of normal speed, is absent from the defender’s command list and never creates a defender report.
Calculation
An attacking spy has 40 scouting power and a defending spy has 20 protection power. If attack does not exceed defence, every attacking spy dies and no information is obtained. Defending spies never die; every surviving attacker returns home after scouting.
Information obtained
Successful scouting reveals settlement units, morale, the wall and resources not protected by the shelter. The chance of seeing buildings and their levels rises with the attacker's scouting-power advantage. Normal scouting can additionally reveal support stationed elsewhere; covert espionage does not reveal it.