The full Pilot Things connector documentation is here.
Each Pilot Things registered sensors have a unique ID. This ID is used to get any information related to a sensor (like measurements, name..etc). There are many ways to get this id.
Get ID manually
The easiest way to get a thing's Id is to look at the URL when you are on the thing's page. The URL end is the ID. (see example below)
Get ID using connector calls
The getThings call could be use to create a collection or a gallery.
For instance this function in a Items gallery property would list all the things informations including the Ids :
You can see thing's measurements in Pilot Things user interface under the Measurements tab on the thing's page. (see example above).