It sounds like you’ve re-invented the “storylet” idea which has been kicking around here for the past few years. E.g. this thread: What is Storylet to you?
Emily Short has written extensively about this sort of structure, which she used in the recent Mask of the Rose (Failbetter Games). See this blog post and its attached and followup links: Storylets: You Want Them – Emily Short's Interactive Storytelling