Command parser sometimes parses list tags as strings
The following command creates a sword with two custom tags, but those tags are strings rather than (as I expected) lists.
/give @p diamond_sword 1 0 {intsAndSpace:[1,2,3, ,4], intsWithLong:[12345678901,1,2,3]}
2015-03-23, 10:45 AM
2016-01-11, 05:13 PM
2016-01-11, 05:13 PM
0
3
-