I have got used to the economy of not be burdened with endless prototypes but I have tested a macro that does reliable arg count testing. The multiple argument macro ".ma" is used to reduce the line count so you could fit more pseudo prototypes into a smaller space.
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include \masm32\include64\masm64rt.inc
.MessageBox MACRO args:VARARG
.ma cnterr .MessageBox,4,args # invoke __imp_MessageBoxA,args
ENDM
cnterr MACRO mname,cnt,args:VARARG
IF argcount(args) NE cnt
echo ****************************************************
echo mname Incorrect Argument Count, cnt Expected
echo ****************************************************
.err <mname Incorrect Argument Count, cnt Expected>
ENDIF
ENDM
api MACRO args:VARARG
args
EXITM <rax>
ENDM
.code
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entry_point proc
LOCAL rval :QWORD
.MessageBox 0,"Statement Version","Test 1",MB_OK
mov rval, api(.MessageBox 0,"Function Version","Test 2",MB_OK)
invoke ExitProcess,0
ret
entry_point endp
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end