@Anonymous User, @Anonymous User @AndrewChapkowski or @RohitSingh2 I also have this question. The documentation for the executeNotebook operation is listed under 'Enterprise Administration', which is a bit confusing when it comes to AGOL, given that AGOL != ArcGIS Enterprise.
So the original question stands - Is it possible to execute an ArcGIS Notebook, hosted on ArcGIS Online, using the executeNotebook operation in the REST API? That is, not using scheduling, but using the executeNotebook operation to run the notebook on demand, by calling it via the REST API.
If so, where is this documented or can someone provide an example? If it is not documented, can we get some guidance please because I would like to do this but am having trouble locating the operation endpoint on ArcGIS Online.