Opensource.com - https://opensource.com/article/18/6/better-api-testing-openapi-specification
If you search the internet for “unexpected API behavior,” you’ll soon discover that no one likes when an API doesn’t work as anticipated. When you consider the increasing number of APIs, continuous development, and delivery of the services built on top of them, it’s no surprise that APIs can diverge from their expected behavior. This is why API test coverage is critical for success. For years, we have created unit and functional tests for our APIs, but where do we go from there?