There isn’t an official standalone "Ren'Py Persistent Editor" tool from the Ren'Py team, but here are your main options: You can manipulate persistent data directly from the Ren'Py console or via a temporary screen.
define config.console = True Then in-game press Shift + O and type, for example: renpy persistent editor
(in options.rpy or gui.rpy ):
persistent.unlock_ending = True to edit values: renpy persistent editor