Some information regarding a TileMap request / response.
The recommended method for detecting missing tiles uses a tilemap
request, which is currently specific to the basemap and elevation tile
services***. It is not yet available as part of ArcGIS Server. This
request is available if the service root info capabilities includes
the Tilemap keyword, as shown above. The tilemap request returns a
JSON structure containing tile presence information for an area of a
The level, row, and column arguments select the level and the top-left
tile location, while the width and height specify the size of the
requested area. The response includes the following: a validity flag;
a location structure with left, top, width, and height values defining
the area; and a data array of size width x height, which contains a 1
if the respective tile exists or a 0 if the respective tile is
missing. The data array is in row-major order.
*** in my opinion - meaning esri content delivery services, not your own basemap/elevation services.
And so on (read the topic, mostly towards the bottom of the page for full reference)