The revelation that J. R. Smith had knee surgery Monday — just four days after signing a rich, new four-year contract — made the Knicks’ investment look instantly suspect and possibly ill-advised. But the surgery was not a surprise to team officials. And the investment was not as extensive as first believed. Smith’s deal covers a maximum of three years, with a total value of $17.95 million, not the four years and $24.5 million that was widely reported, including in The New York Times, last week. The precise terms were confirmed Tuesday by a rival team executive and a second person with access to the contract. Despite the intense scrutiny of the deal, Knicks General Manager Glen Grunwald made no attempt to correct the erroneous reports during a 16-minute conference call with reporters Tuesday. The contract calls for Smith to make $5.57 million next season and $5.98 million in 2014-15, with a third-year player option at $6.4 million. It is still a considerable commitment for a player with a checkered career and now a surgically repaired left knee. But Grunwald betrayed no concern on Tuesday. “We’re pretty comfortable that this is something that’s fixable and won’t present any problems, in certainly the foreseeable future, over the next four years or whatever,” he said. “We’re O.K. with that.” Smith had two procedures Monday, one to repair unspecified damage to his patella tendon and another to deal with a tear of the lateral meniscus. The patella tendon is the more serious of the two and will require an estimated 12 to 16 weeks of recovery — a timeline that could wipe out training camp and possibly the first week of the regular season. Opening night is scheduled for Oct. 29, at the 15-week mark of Smith’s recovery. “We’re hopeful that he’ll be ready by time the regular season rolls around,” Grunwald said, a sentiment he repeated many times. The Knicks have four open roster spots and could add another shooting guard or two as insurance. After Smith, their only true shooting guards are Iman Shumpert and the rookie Tim Hardaway Jr. The timing of Smith’s surgery, which came two months after the Knicks’ season ended, remains a matter of some curiosity. Grunwald said that Smith had been coping with knee troubles since training camp, and that team officials knew in May that surgery was likely. But Smith opted for rest first, a decision the team apparently endorsed. “We were pretty sure that surgery would be required, but we felt we owed it to him to see if we could avoid that,” Grunwald said.