Index: kern_sig.c
===================================================================
--- kern_sig.c
+++ kern_sig.c
@@ -3243,7 +3243,8 @@
 	return (0);
 }
 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
-	    0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
+	    0, sizeof(int), sysctl_debug_num_cores_check, "I",
+	    "Maximum number of generated process corefiles while using index format");
 
 #define	GZIP_SUFFIX	".gz"
 #define	ZSTD_SUFFIX	".zst"