I found following on Wiki to produce PDF out of standalone type(https://wiki.contextgarden.net/Sharing_graphics):

\starttext
 \startMPpage
  draw fullcircle scaled 10cm ;
 \stopMPPage
\stoptext

It generates a PDF but when I open it with Evince, Evince complains that no page was found

and does not show anything. Any help would be much appreciated.