[2] After his playing days, Richardson founded nonprofit organization Project Limestone to provide youth programs that encourage young people to respect their peers, to work together, to define their goals, and set them on a path to achieve those goals.

[2][4][5] As a senior he was named to the 2001 Class 1A All-state high school baseball second team by the Florida Sports Writers Association.

[2] The San Francisco Giants signed Richardson after they took him in the 35th round of the 2005 Major League Baseball Draft.

[1] Baseball America named Richardson the best defensive outfielder in the Giants organization.

[14][1][15] He then played for the remainder of 2009 and the beginning of 2010 for the Schaumburg Flyers of the independent Northern League.

[1] Richardson played most of 2011 for the Mississippi Braves and batted .283/.430 (tied for second in the league, behind Paul Goldschmidt)/.327 with 11 hit by pitch (fifth) and 17 stolen bases in 272 at-bats.

[1] Richardson was called up to the majors for the first time on September 4, 2011, and recorded his first career hit, a single to right field, off Los Angeles Dodgers pitcher Clayton Kershaw in his first career Major League at-bat.

[1] Richardson played three games for Team Great Britain in the World Baseball Classic qualifiers in 2012, going 1-for-10 with a walk.

[19] On September 25, Richardson pinch-ran for Jose Pirela in the bottom of the ninth inning against the Baltimore Orioles.

[21] He underwent back surgery for a bulging spinal disk on March 27, 2015, and was placed on the 60-day disabled list on April 2.

[26] Richardson signed a minor league contract with the Los Angeles Dodgers on April 29, 2016, after being released by the Pirates just two days prior.

[29][28] During the top of the third inning of a game against the San Diego Padres on April 12, 2022, Richardson was ejected for the first time in his MLB career at any capacity after engaging in an argument with Padres third base coach Mike Shildt.

[31] In November 2023, Richardson was hired by the New York Mets to be their first base coach for the 2024 season.