One-size-fits-all doesn't apply to APIs. Instead, they come in all kinds of shapes and sizes. Even if it's true that during design time people try to come up with small APIs, over time they tend to grow. By size, I'm referring to the number of paths that REST APIs have, and not any other measure like the number of parameters, or the length of the responses. So, what can you consider a "normal" size for an API?