The Baseball Hall of Fame asked for Castro's jersey from Wednesday's game against the San Diego Padres. Castro reached base for the 40th straight game with a double in the eighth inning and extended his hitting streak to 10 games.
Castro finished his second season batting .307 with 10 home runs and 66 RBIs.
"I'll continue to work," Castro said. "I know I was better this year and next year I will be even better. I'm going to rest for a while and then start to work out."
Castro said he will play winter ball in the Dominican Republic during December.
"Before that I'm doing nothing. Just rest," he said.
Castro became the youngest player in Cubs history to reach 200 hits and was the Cubs' lone All-Star this season.
ESPNChicago.com's Bruce Levine contributed to this report.