Sensors and services

eGeoffrey calls things the way it was taught in the e-butler school back in time, and this section will introduce you to some of these concepts on the go. Two of the most important components/concepts in eGeoffrey you need to understand are: sensors and services.


A sensor is a kind of virtual notebook where eGeoffrey write things down to remember what is going on and, when we ask any question, it’s used to display information, trigger an alert to keep us aware of something or whatever we want eGeoffrey to do for us.

Sensors/e-notebooks range from those with naive functionality such as task lists or city weather conditions to more sophisticated ones such as those tracking what IoT home devices are measuring.


A service represents something eGeoffrey is capable of and that, eventually, will end up in a sensor/e-notebook for further use. A very simple service/capability might be one accessing an online weather service to get weather conditions for your city, which will be written down in a sensor/e-notebook to finally display it in eGeoffrey’s user interface.

Of course, there are more elaborated services such as those pulling images from webcams and keeping us informed of what’s going on at home when we are away.

Adding new services

Adding new services means providing eGeoffrey with new skills and, in order to make them available, new elements have to be placed in eGeoffrey's accommodation. As already introduced in the "say hi to him" section, the egeoffrey-cli utility helps in that matter and we'll show you how to do so.

In addition to this handy utility, there is an e-butlers online repository with tens of artifacts to give your eGeoffrey new capabilities; this repository is called eGeoffrey Marketplace and it's available at We encourage you to follow the link and have a look at everything that is at a click distance.

Simple sample: weather service


Adding new sensors