The midfielder, signed in January 2016, has been away in Austria for the club’s two-game pre-season tour of the country, which culminated in a 1-0 loss to Mainz 05 today.
Shelvey has a year left on his present deal, but he will trigger another year if he plays three games.
Supercomputer predicts final Championship table - including surprise finishes for Sunderland, Middlesbrough, QPR, Sheffield United and co
Sunderland AFC transfer news: Cats take 'brilliant' ex-Manchester United and Burnley midfielder on trial
Championship transfer news: Interest in £22million man, setback for Arsenal loanee plus Norwich reports
Sunderland AFC transfer gossip: Cats in 'final stages' of deal for 18-y/o eight-cap international winger
Sheffield United suffer injury blow ahead of Sunderland game with 264 goal striker potentially sidelined
Asked if he would like to stay longer than the year he has left, Shelvey said: “I’ve got three games to get another year, and hopefully I should do that this season. I mean, I’d be a bit worried if I didn’t!
"At the end of the day you’re always playing for a new contract, and I’m not thick, I’m not getting younger. I’m 30 years of age – and I look about 40! You just want to be part of it. The only way for this club is up – and a lot of people would want to be in my shoes.
"Positivity’s great around the club. We went through a really bad spell. I’ve been six-and-a-half years now, we know what the craic is around the city – and what you can and can’t do.
"It’s a really good place to be at the minute, the city is buzzing. My missus and kids love it up here.”
On head coach Eddie Howe’s influence, Shelvey said: “He’s constantly on you, reviewing your game, showing you clips. He lives and breathes football – and has instilled that into everyone at the club.
"It’s football, football, football. He’s helped me massively defensively.”