Unclear how to use the radius field

[trobert2]

when specifying the 3rd coordinates[] field, a radius around a set of coordinates (lat/lon) can be provided. What is the unit of measurement for this field? The documentation does not clarify.

When looking around the area, does the filtering happen on the locations values or on the coordinates value?

[Buthrakaur]

@trobert2 you probably discovered already by trial&attempt but it's kilometers