Distinction between actions and sensors

I’m new to openHab so please sympathize. I am working on a REST client and need to decide wether a channel is a sensor or an action. Through my client I am calling for a device and it is returning its JSON with different channels but where can i find an attribute for this decision in the JSON format of the REST API.
Thanks in advance.

I don’t think that information exists. You have to know what the device is and based on that determine whether it is an actuator or a sensor. The only case I can think of where you will know is if the Channel requires a Contact Item which means it must be a sensor. In all other cases there is no way to tell beyond your knowledge that the Channel is to a light switch verses another Channel that is to a temperature sensor.