McDaniels, speaking after a Raiders organized team activity, otherwise revealed little about the first known workout the free-agent quarterback has had with an individual NFL team since he last played in 2016.
"Nah, I mean, I think Derek's pretty comfortable with where he's at," McDaniels said of the recently extended Carr. "I think he knows who he is for us and I know he knows how I feel about him, how we feel about him. I don't think that's really a big thing to Derek at this point."
Kaepernick, 34, worked out for the Raiders on Wednesday, a source told ESPN's Adam Schefter.
Carr, 31, signed a three-year, $121.5 million extension in May. The Raiders have three quarterbacks on their depth chart behind him: recent trade acquisition Jarrett Stidham, free-agent signing Nick Mullens and undrafted rookie Chase Garbers.
"I think he knows this is his football team and he's working like it on the field and he's leading the way that we want him to lead and he's doing all the right things," McDaniels said of Carr. "I couldn't ask more from Derek Carr and very pleased with what he's doing so far."
McDaniels, who's entering his first season as the Raiders' head coach after spending a combined 19 seasons with the New England Patriots, deflected questions about the workout in a similar manner that his mentor, Bill Belichick, often would.
"Just a standard procedure, we will only talk about the people who are on our team," he said. "[General manager Dave Ziegler] and his staff have worked out tons of guys this spring and we really don't make comments about the evaluations that we made or what they looked like, what they didn't look like, strengths and weaknesses, those kinds of things are kind of private obviously for us as we look at things to try to make decisions to make the team better. If players are added to the team then obviously we'll talk about them at that point. I respect the question 100 percent. I understand. But's kind of what we'll stick to."
Kaepernick last played in the NFL in 2016, the year he began protesting racial inequality during the national anthem. The only other team known to have brought him in for a visit since then was the Seattle Seahawks in May 2017. Multiple sources have told ESPN that one of the reasons the Seahawks did not sign Kaepernick after that 2017 meeting was they feared that his popularity and strong résumé would threaten Russell Wilson's standing among teammates in the locker room.
"Honestly, I don't know much about that," Crosby said. "I'm worried about the guys that are here right now, so that's really all I have on that."