oh, i see now. thanks Echo and Iyu :)

those two words can not be interchangeable, 你刚起来don't include any emotion in it, just describe the motion you did, but 你才起来means you are late to get up, you should get up earlier.

There is a slight difference between the two. 你刚起来’s tone is relatively mutual, just describing the fact that u just got out the bed. Anything with 才 is with the wish or emotion that says you should have done that already but didn’t. It might not be an serious accusation as it happens a lot during friendly joking but also means certain degree of unsatisfied feeling. Hope it could be of some help.