Kobe Bryant Divorce -- Busted by Basketball Wives

A secret underground society of trained spies is responsible for feeding intel to Vanessa Bryant that eventually led to her filing for divorce from hubby Kobe Bryant -- not the CIA or FBI ... but the basketball wives of the NBA.

Our sources says Kobe's teammates were blabbing to their women about the superstar's exploits ... and those women in turn gave Vanessa the heads up. We're told talk of Kobe's exploits lately increased in frequency.

According to our sources, the players often swear their wives to secrecy before dishing on their fellow ballers ... but that secrecy is rarely kept. We're told the women all share information about other guys around the league ... in part to ensure word will get back to them if their man ever steps out.

As TMZ first reported, Vanessa filed divorce papers on Friday, after Vanessa learned of what she says is an act of infidelity that became the proverbial straw that broke the camel's back.