In a move that could change how more than a billion people write documents, presentations and emails, Microsoft has discussed incorporating OpenAI’s artificial intelligence in Word, PowerPoint, Outlook and other apps so customers can automatically generate text using simple prompts, according to a person with direct knowledge of the effort.

These goals won’t be easy to accomplish. For more than a year, Microsoft’s engineers and researchers have worked to create personalized AI tools for composing emails and documents by applying OpenAI’s machine-learning models to customers’ private data, said another person with direct knowledge of the plan, which hasn’t previously been reported. Engineers are developing methods to train these models on the customer data without it leaking to other customers or falling into the hands of bad actors, this person said. The AI-powered writing and editing tools also run the risk of turning off customers if those features introduce mistakes.