"NPC Creator is a simple tool for Stardew Valley for users who wish to create their own custom NPC without the hassle. Entering information in the fields and clicking buttons takes out hours of typing and searching for code to build a basic NPC. It is a good ground-level building tool that will give your NPC everything it needs to be a part of the game. While it will do some advanced tasks, you will have to learn to do the more advanced tasks such as Map Building, sprite creation, and token-based patching. This creator was made with the beginner in mind."
Documentation and guide: https://github.com/MissCoriel/NPC-Creator/wiki