The key regions the analysis ran against, in time order. Roman numerals, harmonic function and note safety are all judged against the region covering the beat, so a piece that modulates is not read against the key it started in for every bar after it leaves.
The key held longest across ArrangementAnalysis.keys, whole: the pitch classes with the spelling and the scale form the regions carry.
Notes clashing with the sounding harmony, worst severity first.
The full result of analyzeArrangement.