How to add Finder/Services menu items to own macOS contextual menu

Question

When a file is right-clicked in the macOS Finder, a contextual menu like this shows up. It contains items at the bottom from macOS Services. I'm talking about services from third party such as (in this case) iTerm and Find Any File. How would I go about adding such items to a contextual menu in my own macOS app? Is there a documented API to do this?

I know this can be done, because it's implemented in at least one other application, see for example the following contextual menu in Find Any File:

Answer 1

macOS provides App Extensions for products to integrate with the OS. The programming guide lists the different extension points that can be utilised, along with a description of their purpose.

Based on the example you've provided, it may be the Finder Sync extension that you're looking for, as the documentation states for Finder Sync:

Badge local OS X folders to let users know the status of items that are remotely synced. You can also implement contextual menus to let users directly manage their synced content.