“This has given us a real opportunity to hear partners’ voices and say, ‘Are we being clear enough, and are our intents and practices being followed?’ ” Mr. Burrows said in a phone interview.

Though Mr. Burrows vowed in his letter to revise the company’s scheduling software, he could not say exactly how in the interview.

The change comes amid a growing push to curb scheduling practices, enabled by sophisticated software, that can cause havoc in employees’ lives: giving only a few days’ notice of working hours; sending workers home early when sales are slow; and shifting hours significantly from week to week. Those practices have been common at Starbucks, and many other chains use even more severe methods, such as requiring workers to have “open availability,” or be able to work anytime they are needed, or to stay “on call,” meaning they only find out that morning if they are needed.

Some Starbucks workers greeted Thursday’s announcement with mixed feelings. “I’m generally pretty positive about Starbucks,” Amber Tidwell, a barista in Fresno, Calif., said in a phone interview.

“Encouraging managers not to rely entirely on the automated software is the best thing they can do. But I’m doubtful of how many managers will actually do it,” she said, because of the wide variation in how managers at different stores treat their employees.