In order to improve the initial experience of using painless for runtime fields and generally improve the developer experience, we should provide examples and quick functions within the editor itself and not force the user to go to the documentation right away.

Ideas:

Include tabs for editor and quick functions

Provide common use cases easily accessible similar to our formula UI in Lens. After choosing a quick function, we could fill the editor view with that script to teach how the code is structured. (Perhaps the tab order need to be switched?)

Avoid a blank box at start and prefill with some examples