Some tasks, such as ‘Submit Scan’ in the Medbay, have a visual animation/indicator that other players can see, thereby allowing them to ‘vouch’ for whoever did the scan. Other tasks don’t have any indicator, leaving you to guess if the player standing by a console or wall is legitimate or just pretending.
I know that sometimes you can determine if a task was completed based on the ‘Completed Tasks’ tracker/bar increasing, but this isn’t reliable with larger player numbers, and the impostors can see it too, so it can be gamed.
Which tasks can be visually verified while underway, or at completion? And for a given task, what visual indicator should one be looking for?
The following tasks have visual indicators:
MedBay: Submit Scan (The Skeld, Mira HQ, Polus)
Shields: Prime Shields (The Skeld)
Upon completion, the shields to the lower-right of the room will activate and turn yellow. If this task was already completed, completing it again will cause the lights to pulse.
Storage Room: Empty Garbage (The Skeld)
This is a two-part task. The second part always takes place in the Storage Room, and upon completion, you can see garbage ejecting from the bottom of the ship.
Weapons: Clear Asteroids (The Skeld, Polus)
When the crewmate fires the weapons (by clicking / tapping on the screen), the weapons outside of the Weapons room will fire a laser. On The Skeld, these are on the right of the room ; on Polus, these are outside the room, on the left, and are visible from outside.
* Image credit: Among Us Wiki