YouTube is rolling out its "SmartReply" technology to YouTube, meaning that comments you see on the site might not actually have been written by a human.
The technology analyses messages and then uses artificial intelligence to guess what a person might want to say in response to them. Users can then select that response and post it, without ever having to write anything out for themselves.
It has already appeared within Gmail and Android's Messages app, and is open to developers who can integrate it within their own app.
But it is now coming to YouTube, which represents the most public place any messages written by the SmartReply software will be seen.
If a person comments on a video asking when there will be more of them, for instance, the SmartReply system might suggest that the creator replies saying "The next video is coming in August". They will then be able to post that – and the commenter will receive a notification that they been responded to, without necessarily knowing it was written by a piece of software.
Google said that rolling out the AI to YouTube posed a particular challenge, because of the nature of messages that tend to go on the site. Unlike the lengthy and formal language of an email, YouTube comments tend to include "language switching, abbreviated words, slang, inconsistent usage of punctuation, and heavy utilization of emoji", Google noted.
But the decision was made to bring it to YouTube users because creators often receive a huge volume of responses to their videos in the form of comments, and the SmartReply feature could be used to allow them to more easily stay in touch, the company said.
As with other SmartReply messages, the YouTube replies will still be chosen by a human, who will pick from different options presented by the software. The technology will not post messages itself – but will have written them.
YouTube creators will also be able to edit or expand on the messages if they wish. They will also only be presented with the option when "it is likely that the creator would reply to the comment and when the model has a high chance of providing a sensible and specific response", YouTube said, so that it is not offering suggestions unnecessarily.