Plug-in API - Tonal pitch classes and MIDI values

I'm looking for some clarification of the behaviour of the JavaScript plug-in API when altering TPC and MIDI values.

How would musescore behave if I were to alter the values so that they are inconsistent?

Specifically, what are the rules used to infer the correct notation from a MIDI value that is inconsistent from the TPC.

I'm looking to develop a plug-in that adds highly chromatic passages derived from melodic sequences and I'd like to fix it so that all passages are derived from the same (pos. user defined) chromatic scale (there are quite a number!) to minimise the number of accidentals duplicated, and ease the reading.

Thanks