Hamilton was heavily self-critical at times during the 2013 season, and also raised eyebrows with some of his forthright radio conversations with the Mercedes crew.
After the season-ending Brazilian Grand Prix he claimed he had an "average" year, and said he would redouble his efforts over the winter ahead of F1's big rules shake-up this season, but Wolff said he found Hamilton nothing but straightforward and very well-adjusted away from the racetrack.
"First of all, he has a straight and nice character," Wolff told AUTOSPORT.
"So generally it is a pleasure to work with him - and it is also a pleasure to work with him because he is very competitive.
"Rarely do you find people who are so competitive and then on the other side not f**ked up. And he is not."
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Asked if he felt Hamilton needed more 'looking after' than other drivers, Wolff replied: "He is authentic. And sometimes authenticity bites you. But he also learns.
"And what I like is the way he is taking on the advice, and believes it is good for him. We are trying to be very open with each other."
Wolff's colleague Niki Lauda believes Hamilton, who won in Hungary but only scored four more podiums despite starting five races from pole position, was too harsh on himself during 2013.
"Lewis had his ups and downs but his talent and his speed and his attack is there, there is no question about it," Lauda told AUTOSPORT.
"He won one race in Budapest in an outstanding manner. Nobody could have done this there better than he did."