The field ‘totalFrames’, total number of frames available, is mandatary in StackTraces response for VSCode extension that implements DAP and declares capability 'supportsDelayedStackTraceLoading':
"The debug adapter supports the delayed loading of parts of the stack,
which requires that both the 'startFrame' and 'levels' arguments and the
'totalFrames' result of the 'StackTrace' request are supported."
Lack of this field makes VSCode incorrectly display stack traces information