In the work, the authors offer a mechanism to determine the scale of actions in good faith of the parties of the obligation at stages of its formation and fulfilment, which allows determining the scope and limits of judicial discretion in resolving a disputable situation. This mechanism corresponds to the general approach of perception of good faith in the objective sense using the author's theory of "particular life circumstances", which is based on the external and internal (substantial) assessment of the behavior of obligation participants made by the court with consideration of the facts of the case. It is established that the content of the scope of actions in good faith of the parties at the stage of formation of obligations consists of standards allowing to give an external and internal (substantial) assessment to the behavior of the parties. The essence of the external assessment consists in the need for the participants of civil transactions to comply with formal legal requirements. The internal (substantial) assessment is expressed in the need for the behavior of the participants of obligation relations to comply with the standards of good faith as the expected conduct in factual circumstances. It is determined that during the determination of compliance of the parties' behavior with the standards, which allow to give an internal assessment to such a behavior, at the stage of obligation formation, the role of judicial discretion is significant: the court has the mechanisms of determination of the good faith of behavior based on comparison of property interests of the parties in the formation of an obligation. During assessment of the behavior of the participants of civil transactions, of importance is the application by courts of legal customs that act as a landmark in establishment of standards of actions in good faith. The authors conclude that any violation of obligation conditions excludes the presumption of good faith. However, defects of execution, which directly affect the behavior of one of the participants of the obligation, do not abolish the presumption of good faith until the contrary is proved. The basic principles of the legal institution of obligation fulfilment determine the features of establishing standards of actions in good faith of the parties of the obligation from the viewpoint of the internal assessment of their behavior.

В развитие авторской теории восприятия добросовестности (в объективном смысле), а именно теории «конкретных жизненных обстоятельств», показаны особенности определения масштаба добросовестного поведения сторон обязательства на стадиях его возникновения и исполнения; представлена взаимосвязь ключевых в гражданском праве понятий: «принцип добросовестности», «добросовестность» и «добросовестное поведение»; определены пределы судейского усмотрения при разрешении спорных ситуаций.