A native of Los Angeles, California, Kirby attended Harvard-Westlake high school then went to Pomona College where he was a PPE (Philosophy, Politics, and Economics) major. He spent the year after graduation teaching English in South Korea and when he returned moved to San Francisco to get his JD at UC Law San Francisco (formerly UC Hastings).

His first agency position was at Charlotte Sheedy Literary, at that time an affiliate of Sterling Lord Literistic. He then moved to Vigliano Associates where he gradually started representing his own projects. In 2008, he joined Endeavor which the following year merged with William Morris. He stayed at WME for five years before joining Janklow & Nesbit.

Kirby represents fiction across the spectrum; both literary and commercial. He’s most interested in receiving manuscripts that straddle the fence a bit, with upmarket expression combined with a genre element or plot device. His commercial interests include book club fiction, thrillers, mysteries, suspense, horror, and grounded science fiction. When it comes to straight literary work, he’s drawn to rich, sweeping stories that try to encompass a time or a place or tightly written, narratively innovative stories or voices with award potential.

He represents a range of nonfiction working with leaders and journalists in the areas of science, business, culture, and current affairs. He’s also known for representing pop culture, in particular music and comedy.

Kirby is currently a board member of the Asian American Writers' Workshop. He lives in Phoenix, Arizona with his wife and two kids.