COUNTED_REASON_CONTEXT - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers
#ifndef _NTPOAPI_H

// wdm
typedef struct _COUNTED_REASON_CONTEXT
{
    ULONG Version;
    ULONG Flags;
    union
    {
        struct
        {
            UNICODE_STRING ResourceFileName;
            USHORT ResourceReasonId;
            ULONG StringCount;
            _Field_size_(StringCount) PUNICODE_STRING ReasonStrings;
        };
        UNICODE_STRING SimpleString;
    };
} COUNTED_REASON_CONTEXT, *PCOUNTED_REASON_CONTEXT;

#endif

View code on GitHub

This structure is documented in Windows Driver Kit here and here.