changed property
Changed says whether the run produced any commit. It is INDEPENDENT of OK: a run can succeed and change nothing (there was nothing to do), and a run can fail after committing some of its work. Two questions, two booleans.
Please note: This property should have been non-nullable! Since the specification file does not include a default value (using the "default:" property), however, the generated source code must fall back to having a nullable type. Consider adding a "default:" property in the specification file to hide this note.
Implementation
bool? changed;