Ask HN: What makes a great API documentation in your opinion?

There are a lot of different ways to do documentation. There are the basics like having good SDK/libraries references. For example, [Stripe's famous 3 panels view](https://stripe.com/docs/api) is one of many ways of displaying that information. It does get quickly blurry when you introduce topics like: - Explaining the main concepts of the products/API - Quick Start Guides (multiple languages?) - How-tos for the main use cases - Tutorials such as how to do <use_case_x> with <specific_language_or_framework>. Do you even include that in the docs? Then there are the features of docs: - Button to try this function/API call - Includes the user' API keys in the sample code if they are logged in - all of the content in one very long page or split it up. - etc So HN, what do you like to see in an API documentation? from little features, cosmetics, layout or how to structure the content. I want to hear about it!