Facebook M, the text-based virtual assistant that used human workers to train an artificial intelligence system, is ending the human-assisted part of the service after two and a half years. From a report: The human-enhanced version of M, which was available through a bot on Facebook Messenger, only ever became available to about 2,000 people living in California. The final day of the will be January 19th, Facebook said, and contractors who worked on it will be offered other jobs at the company. First introduced in August 2015, aspects of the service will live on through M suggestions, which offers fully automated suggestions for payments, making plans, and sending stickers through Messenger. When it launched, Facebook described M as a "beta" and suggested the human-powered assistant would come to more users over time. But it never did. Upon shutting down the human-powered M, Facebook described it as an "experiment."