1. A system, comprising: at least one computer hardware processor; and at least one non-transitory computer-readable storage medium storing processor-executable instructions that, when executed by the at least one computer hardware processor, cause the at least one computer hardware processor to perform: automatically generating an object hierarchy comprising a plurality of objects corresponding to active graphical user interface (GUI) elements of at least one application program, the at least one application program including a first application program and a second application program, the generating comprising: identifying active GUI elements of the at least one application program; identifying relationships among the active GUI elements; generating, based on the identified active GUI elements and relationships, a first portion of the object hierarchy comprising objects corresponding to active GUI elements of the first application program and a second portion of the object hierarchy comprising objects corresponding to the active GUI elements of the second application program; accessing a task comprising a sequence of actions; performing said sequence of actions by: controlling the first application program to perform a first action in the sequence of actions using the first portion of the object hierarchy; refreshing a portion of the object hierarchy according to any changes in the active GUI elements after the first action is performed; controlling the second application program to perform a second action in the sequence of actions using the second portion of the object hierarchy; and refreshing a portion of the object hierarchy according to any changes in the active GUI elements after the second action is performed; and during performance of the sequence of actions, generating a visual representation of already-performed actions in the sequence of actions; storing the visual representation; determining that an error in performance of the sequence of actions has occurred, the error preventing completing automated performance of the sequence of actions without human intervention; and when it is determined that the error in performance of the sequence of actions has occurred, providing to a user the visual representation.