Google Data Studio pagination in custom connector getData: undocumented

In the getData() function I'm sometimes seeing some calls with a request that contains

pagination={startRow=1.0, rowCount=100.0}

and they seem to be ones that also have

scriptParams={sampleExtraction=true}

However, I can't see any documentation on pagination. Is this a stable feature? Will there ever be a request for a startRow that isn't 1.0?

I'm asking since to make robust pagination for some of our data sources may not be trivial, so would like to know if it's worth the effort.