Andy Richter has some unfinished business.

Richter, who appears this Sunday on TBS as part of its “Very Funny Festival” coverage, said there was never any question that he would join Conan O’Brien’s new yakker at the basic cable net.

“I’m doing the TBS Conan show because I went back to work for Conan on ‘The Tonight Show,'” Richter said. “But that story ended unnaturally.”

Richter served as O’Brien’s sidekick on “Late Night with Conan O’Brien” from 1993 to 2000. After that, Richter left to pursue acting, landing critically acclaimed but little-seen shows like “Andy Richter Controls the Universe.”

When Richter was named O’Brien’s announcer on the new “Tonight Show” in 2009, it was hyped as a big late-night reunion.

“There was a notion of stability” to the “Tonight Show” gig, said Richter, who was expecting a steady paycheck for at least a decade. But when O’Brien and NBC abruptly parted ways in January, that idea was shattered.

“I didn’t want them to end that story of me and Conan getting back together,” said Richter. “I had come back to work with a friend.”

That’s why Richter hasn’t gone anywhere, instead opting to go on tour with O’Brien during the host’s recent “The Legally Prohibited From Being Funny on Television Tour.”

“It was cathartic,” Richter said of the tour, which recently wrapped. “It was like rock and roll fantasy camp. Conan needs to keep busy. He runs at a very hard RPM and needs to occupy his time.”

Richter said he didn’t take the turn of events at NBC as hard as some, given the unfortunate outcomes of his primetime endeavors.

“I had an advantage compared to a lot of people at ‘The Tonight Show’ in that I experienced being on a show that everyone liked suddenly going away,” he said. “I had had that experience of riding high, feeling great to absolute crushing rejection.”

That’s why Richter said he wasn’t completely surprised by what happened. But nontheless, “it made me redefine stability again.”

This time out, O’Brien owns his show on TBS — which Richter takes as a sign of finally being able to count on a long-term job.

“(Turner) has been nothing but supportive,” Richter said. “We can do whatever we want and be ourselves. And it feels like we’ll be out of that ratings race.”

Richter said planning for the new show hasn’t really started in earnest yet — but he noted that the O’Brien team has been putting on late-night yakkers for 17 years, and doesn’t need a lot of practice.

“All I know at this point is that we have a studio at Warner Bros.,” Richter said. “Beyond that, we’ve been occupied with the tour.”

And what about lingering issues from the NBC debacle?

“At this point, it’s old news to me,” Richter said. “It’s like a bad breakup. Once you get over it, you don’t want to dwell.”

Not that he’s hedging his bets, but Richter has another potential gig in the works: The comedian just taped a pilot as the new host of “Pyramid,” which is in contention for a weekday afternoon slot on CBS. (Should it go to series, Richter would easily be able to juggle both that and the O’Brien TBS show, as gamers are usually taped sporadically.)

As for “Team Coco presents Conan’s Writers Live,” Richter said he’s hosting it as a way to give more exposure to O’Brien’s writing staff.

The writers first produced the show on stage in Los Angeles in the weeks after O’Brien’s “Tonight Show” ended in order to cultivate an outlet for ther humor.

“When Conan got involved with TBS, the channel asked if there was anything he wanted to do with the comedy fest in Chicago,” Richter said. “We decided, well, the writers already do this thing… The purpose is to showcase more of their personal work.”

Scribes participating include Dan Cronin, Andres du Bouchet, Josh Comers, Brian Kiley, Matt O’Brien and Deon Cole. Jimmy Pardo and Reggie Watts, who opened O’Brien’s stage show, are also a part of it.

“Conan’s Writers Live” airs Sunday, July 27 on TBS.

(Rachel Abrams contributed to this report.)