Is there any API to create extension for iWork apps on macOS (Keynote, Pages)?

We’re developing a corrector and have been using Accessibility SDK to get access to the text object within those apps, but are being blocked by the initial unavailability of that framework. Integration would be much easier was there an API.
There is not currently an API for creating extensions of the iWork applications. If there’s something you’d like to do with them that’s not available via their scripting interface or via Accessibility, please file feedback describing your use case.

To Apple,

It has been 2 years; has Apple chosen to make an API available to connect or extend its capabilities to another app? What are the references for scripting interface or Accessibility?Can these interfaces be utilize by another app to do what an API does? Thanks.

I wrote an ebooks about Keynote, Pages and Numbers scripting. Text item manipulation is a very easy task for AppleScript.

https://piyomarusoft.booth.pm/items/4049167

Select like red colors text items on current slide on Keynote document https://www.youtube.com/watch?v=3ykU_RQA-Cg

Mark strings sandwitched by start_string and end_string in current Keynote slide https://www.youtube.com/watch?v=aIkQh7ho3WA

Compiling Keynote text item as "AppleScript" program and apply syntax colors demo AppleScript https://www.youtube.com/watch?v=HXJGRBrUzyE

Is there any API to create extension for iWork apps on macOS (Keynote, Pages)?
 
 
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