The next assistant in many offices could be named Alexa or Cortana.

In 2016, Silicon Valley obsessed over how text-based bots in apps like Slack could make employees more efficient, turning complicated tasks or forms into conversational texts. Now, following the success of Amazon Inc.’s Alexa and Alphabet Inc.’s Google Home, people in the technology industry are increasingly thinking about how such voice-activated devices can be made useful in the workplace.

The products aren’t quite ready for office prime time yet. The workplace offers challenges that experts say intelligent assistants built for home use so far haven't effectively met, mostly in the area of voice recognition.

Still, some potential customers aren’t waiting. Workers at Goodwinds Inc. in New York City, for example, have used an Amazon Echo attached to the office ceiling for such tasks as adding events to their calendars and setting reminders for meetings, says Vinay Patankar, chief executive of the workflow-management startup.

And sometimes they use it just for fun. When someone makes a big sale, they say, “Alexa, play the money song,” Mr. Patankar says. Then “Cash Machine” by Big Baby D.R.A.M. begins to play. Each day, the speaker also reminds everyone it’s time for lunch with the voice of rapper Missy Elliott.