Kara DioGuardi Kara DioGuardi

If you didn't know, Kara DioGuardi's writing a memoir — A Helluva High Note: Surviving Life, Love, and American Idol — where she'll wax on about her time on TV's No. 1 show. It's out on April 26.

Until then, please, no questions about Idol.

Kara DioGuardi to pen memoir about American Idol

Facing reporters Thursday to promote her upcoming Bravo series Platinum Hit, a competition aimed at finding the next great songwriter, DioGuardi refused to talk Idol.  Asked for her opinion on Idol's decision to let contestants sing original music, she said: "I really don't know what they're doing... but I can tell you that songs are the backbone of the music industry and this show is about finding hit songs."

Kara DioGuardi to judge new Bravo show

Later on, she was asked if she could clarify the circumstances under which she left Idol. "I'm happy to address that with you privately, today I'm really here for Platinum Hit," she said amid "boos" from the room. She backed up: "American Idol was an incredible experience, but I'm here as a hit songwriter. I've sold over 150 million albums."

So there you have it. As for Platinum Hit, the show will follow 12 aspiring songwriters as they write songs alone and collaboratively in a range of genres, from rap to rock 'n' roll. DioGuardi serves as a judge alongside Jewel, who also hosts.

Kara DioGuardi exits American Idol: "Now is the best time to leave"

The show "reveals a very secular world that people don't get to see," Jewel said. Contestants will have to perform their original material, but won't be judged on their singing. "We're not looking for people to be great singers... We're looking for someone who can write hits for Carrie Underwood, or anyone."

DioGuardi says the collaborative challenges reflect how most hits are written today. "I could walk into a room with total strangers and for three hours we're totally vulnerable," she said. Executive producer Glenda Hersh said that's what will make for compelling TV. "Songwriting is an honest, emotional act."

"And then you add the sex, and it's one crazy show," DioGuardi joked.

Platinum Hit will premiere this summer. Will you check it out?