The liner notes on many albums go to great lengths to tell you who played what instrument on which song. The notes to the Rolling Stones' Sticky Fingers would seem to be one of these; they make clear, for example, that Ry Cooder played guitar on "Sister Morphine" and Nicky Hopkins played piano on "Sway" and Bill Wyman played electric piano on "You Gotta Move" (which has no bass part).
But in the cases of "Sway" and "Moonlight Mile," you don't get to find out everyone who played on those tracks. Both of those credits read "Paul Buckmaster: Strings," and while I suppose it's possible that Buckmaster played every string part on those songs, that wouldn't be a very efficient use of studio time, would it? No, I think anonymous violinists played the strings on those songs, and Buckmaster arranged the charts for them.
The only times you see a string player credited on a rock & roll record is when they're playing solo, like Scarlet Rivera or the ubiquitous cellist Jane Scarpantoni. If they're playing as part of a team, they're out of luck.