No, Google does not publish an API.

My approach is to replicate what Chrome does, and from looking at the gkeepapi Python module, it seems that it replicates what the Android app does.

Currently, our two applications are different, as gkeepapi seems to be mostly concerned with creating/manipulating notes while I'm mostly concerned with getting a complete backup of Google Keep notes, ideally including images etc.

My module currently still needs/uses WWW::Mechanize::Chrome for conveniently automating some things and basically running the Google Keep Javascript code, but at least some parts should work without Javascript already.