Facebook has slowly been transforming its standalone Messenger app into a platform in its own right, and the introduction of intelligent chatbots has played a major part in that. But as more and more brands and developers look to introduce their own chatbot, Facebook has decided to introduce a number of rules to help weed out those that might generate spam.

While Facebook already had a number of guidelines in place for those creating chatbots for Messenger, the latest move formalises those rules, with perhaps the most important one being that Messenger API experiences can only respond to users who initiate conversations.

These replies must be made within 24 hours, and once more after that for re-engagement purposes. Subscription Messaging that delivers, for example, a daily weather forecast, stock reports or news, requires an opt-in, and is limited to a small number of use cases including health and productivity.

All developers must submit their Messenger integrations to Facebook for approval, which will be completed by the social network within five days. Existing developers who have already created bots have three months to comply, or six months in the case of subscription bots.

The full rules for chatbots can be found here, but the overall aim is to prevent Messenger from becoming overrun with chatbots delivering spam who drown out the human users or services that consumers actually want.

“These updated policies will provide more defined engagement models on the platform, including time-based criteria for businesses to respond to messages and standards for subscriptions in Messenger,” said Set Rosenberg, product manager at Facebook. “We continue to put people in control of their experiences in Messenger.”

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