Called Claude Fable 5, it is twice as expensive as the company’s previous flagship system.

© Jason Henry for The New York Times

The company hopes to raise billions in a highly anticipated public offering that could unlock a new generation of tech industry wealth.

© Andres Kudacki for The New York Times

A San Francisco start-up called Arena found that people are most likely to use A.I. agents on the job, particularly if they are in the tech industry.

© Brennan Smart for The New York Times