I first wrote about the API Hierarchy of Needs in 2013. I got inspired by Maslow’s hierarchy of needs and defined the layered needs of an API consumer.

The API hierarchy of needs. Inspired by Maslow’s hierarchy of needs, the pyramid represents the layered needs of API consumers by order of importance.

The layers are stacked by order of importance, with the one with the most priority at the very bottom.

• Usability: is your API easy to use by new consumers?
• Functionality: does your API work as advertised?
• Reliability: does your API perform consistently over time?
• Proficiency: does your API increase the skills of consumers?
• Creativity: can your API be used in unexpected and creative ways?