Richarlison scored both goals, the second a sublime leaping volley, but that was overshadowed by Neymar limping off late on with an ankle injury and appearing emotional on the bench.
The forward has struggled with ankle problems in the past, but Tite does not believe the issue is serious, telling a press conference: "We are confident that Neymar will continue playing in the World Cup."
Brazil doctor Rodrigo Lasmar added: "We need to wait 24-48 hours in order to have a better assessment. We have not scheduled any MRI and tomorrow we'll have a new assessment."
Defender Danilo also picked up an ankle problem, hobbling through the final minutes.
Neymar spent 11 minutes on the pitch after suffering the injury before being substituted.
Asked why he had not made the decision earlier, Tite said: "I didn't see Neymar was injured. The capacity he has to overcome it, it tricked me. I only saw it now when I watched the video."
Brazil were tepid in the first half, creating only a couple of clear-cut chances, but improved significantly after the break, with Richarlison justifying his selection ahead of a host of other talented forwards.
Tite said: "I think this was an important victory with many wins in the same game. (In the first half) this wasn't our normal standard. In the second half we repositioned people and we improved technique.
"I had six, seven names to call (on) and, whoever I called, we would have had a great team. Richarlison is fantastic. We see how he controls a ball, it goes up and he adjusts all his plans."
Serbia coach Dragan Stojkovic was disappointed by his side's second-half display, saying: "I think we were on an equal level in the first 45 minutes, I didn't see they were much more dominant at that stage.
"But in the second half we fell physically and we were no longer a team. And of course Brazil knew how to take advantage of this because they have excellent players."