The app is assiting the use of tone indicators.
You can either extract the used tone indicators from a message directly by right click on a message -> app -> Get Tone or look up specifc tone indicators by using the /tone command.

If you are unsure which tone indicator should be used you can take a look at a list of all common tone indicators and their meaning with the /tone-list command.

All command responses only show up for the person issuing them so that you wont interrupt the flow of the chat.

Tone Indicator

Look up tone indicators used in messages.

Stemmen voor Tone Indicator