Optimizing the usability of REST API reference documentation

Sammanfattning: With an increasingly growing demand for accessible data, the amount of REST API:s worldwide is growing. All REST API:s come with some form of reference documentation, which is crucial for the comprehension and usage of the API. Every API provider should therefore consider the usability of their reference documentation, to facilitate the learning and usage of their product. This master's thesis was performed in collaboration with Homepal AB, a startup company within the real estate industry. The master's thesis explores what features and properties should be included in a reference documentation order to support the needs of the end users. Furthermore, it aims to investigate how different types of developers use reference documentation differently. These learnings were then applied to a prototype, that was subject to evaluation in several stages. By using a user-centered design process and an iterative approach, with interviews and and a usability study, combined with literature studies of former research, heuristic analyzes of example documentation, along with insights from the private sector, prototypes of different levels were created and iterated with the goal of creating a final prototype illustrating the learnings, that then could be used as inspiration for improving the reference documentation of Homepal. The result of the design process, and the final prototype, was mainly evaluated through user observation and feedback, as well as the usage of the System Usability Scale. The prototype was highly and widely appreciated among the users, and received an average SUS score of 95.