1. A method, comprising: providing, via a user interface, a graphical representation of a communications network; receiving, at a first network device executing a device simulation tool, a selection of a second network device in the communications network selected via the user interface; providing, via the user interface, a user-selectable first list of a plurality of use cases, a user-selectable second list of a plurality of scenarios, and a user-selectable third list of a plurality of error conditions associated with operation of the second network device or the communications network; receiving, at the first network device, a selection of at least one use case, scenario or error condition associated with operation of the second network device or the communications network selected from the user-selectable first, second or third lists, wherein receiving the selection of at least one use case, scenario or error condition, further comprises: receiving, via interaction with the user interface, the selection of the at least one case from the first list of the plurality of use cases, the at least one scenario from the second list of the plurality of scenarios, or the at least one error condition from the third list of the plurality of error conditions; executing a network simulation of the communications network based on the selected at least one use case, scenario or error condition; generating a call flow diagram, that involves the selected second network device, based on the executed network simulation; and providing a graphical display of the generated call flow diagram.