According to IGN, Marvel Studios' president Kevin Feige talked about Spider-Man's arrival in the Marvel Cinematic Universe during a Q&A for the upcoming release of Avengers: Age of Ultron. Calling the agreement with Sony to bring Spidey into the MCU "amazing," the studio chief said, "I think Spider-man can serve great purpose in our universe and that's where he belongs."
To Feige, part of the character's unique identity is that he lives in world already populated by costumed heroes and becomes "a totally different kind of superhero when compared against all the other ones in the Marvel universe at the time."
He also said, "the most important thing as a standalone is relaunching Spider-Man in his own standalone movie with his own storylines that fits into this universe. That is job number one for us." Though the shared universe is a great aspect of the MCU, Feige said, "it doesn't drive the train."
Similarly, despite Spidey's debut in Captain America: Civil War, Feige said the film is still Cap's movie and a follow-up to Captain America: The Winter Soldier. "There were a lot of characters in The Winter Soldier, but it felt like a very singular and relatively simple thriller. Civil War follows in that same way," he explained. Though many of the established heroes make appearances, not every character will get a full story arc in the film, just "enough that their presence is felt and important, but that the very clear single story that is being told is being served at all times."