Testing APIs is getting more and more complex and therefore there’s lots of tooling out there to assist.
One of the better known-tools is Postman, but I am annoyed of it lately. The UI is really slow and sometimes it is quite painful to get around with it, especially with the collections. A plus is the handling of tests.
The more light-weight version Hoppscotch (formerly known as postwoman) makes the UI a bit easier to handle, because it is browser-based without the whole electron bloat, but still kind of weird.
So far I Testmace makes a good impression on me, but unfortunately I don’t have it on my testing rig and cannot give it a try for real things.
The same is true for Insomnia, it looks promising and I really dig the idea of separating the designing stuff from the base testing tool.