Function debug_parameters 

pub fn debug_parameters(
    report: &DebugReport<'_>,
    spans: SpanLookup<'_>,
) -> Value

The Parameters response of $transform with debug=true (debug.md): return when there is a result, traceStatus, the trace events with their text positions where spans knows them, and an outcome with the failure, the reason events were left out, and values left out of the result.