However, it's important to consider the context. If you're referring to the small green flower buds used as a condiment, then "kaparis" is accurate.
If you're talking about "caper" in the sense of "to act in a playful or mischievous way", then there are several translations depending on the nuance, including:
* Magbiro (to joke)
* Mag-inarte (to be coy or flirtatious)
* Magpakulit (to be stubborn or playful)
It's best to provide more context so I can give you a more accurate translation.