When attempting to write this command

/particle entity_effect{color:[1,0,0.5,1]} 

the game returns the following error:
"Can't insert TAG_Int into list of TAG_Double"
This is because the game expects you to write:

/particle entity_effect{color:[1.,0.,0.5,1.]}  

I think you should be able to place 0 or 1 into these brackets as it is fairly obvious the intent is to treat them as 1. and 0.
This over restrictive parsing also makes using command macros with this custom color a bit more cumbersome