Definition
The Instagram messaging API lets a business read and reply to Instagram Direct messages on its Instagram professional account from its own software, such as a shared inbox or chatbot, within Meta's messaging windows.
Meta offers Instagram messaging through the Instagram API (with Instagram Login or with Facebook Login through a linked Page) and through the Messenger Platform. The account must be an Instagram professional account (business or creator).
The business can message a user only after that user has messaged the account. Meta's documentation says the app has 24 hours to respond to a user's message. A Human Agent tag allows a manual response outside that window for escalations.
Typical uses are answering product questions from posts, stories and ads, replying to comments with private replies, and qualifying leads before handing them to sales. Messages in the Requests folder that have been inactive for 30 days are not returned by the API.
As with Messenger, there is no outbound broadcast to people who have never messaged the account. Growth comes from content and ads that prompt people to send a DM.