virtual-assistant | based virtual assistant that tells you all you need to know | Chat library

What the user is supposed to do/say in the dialog to see that card?

Start a new converstation after having previous interacted with the bot. For example, using the out-of-the-box VA, if you use the 'test in webchat' blade on Azure, you'll get a welcome card, and a prompt to enter your name. Later converstations, if you 'restart conversation' in that pane, you won't be prompted to enter your name, you'll get just the card.

In other channels, it would be as simple as sending 'hi' or 'are you there' to a bot to restart the convo after the bot has timed out (ie, the user hasn't messaged the bot after some time). This is known as a 'welcome card'.

For generic bot welcome messages: https://docs.microsoft.com/en-us/azure/bot-service/bot-builder-send-welcome-message?view=azure-bot-service-4.0&tabs=csharp

For VA specific welcome messages:https://microsoft.github.io/botframework-solutions/virtual-assistant/tutorials/customize-assistant/csharp/2-edit-your-greeting/

There isn't anything official for V4 bots like this. I don't believe I've seen anything unofficial, either.

That being said, we generally recommend something like:

1. On each message, start a synchronous timer. You can do this in the bot, but it would be better to do outside of the bot, like with Azure Functions or something. The rest of this answer will assume the timer is outside of the bot. Ensure the timer also keeps track of the conversationReference related to the timer.
2. Restart the timer each time the user matching that conversationReference sends a message
3. Once the timer expires, send an event to the bot with the user and conversation information (maybe through ChannelData), letting the bot know the timer has expired. You could also create a separate endpoint and monitor there, so you don't need the activity scheme; instead of /api/messages, you could use something like /api/expiredTimers.
4. Once the expired timer event is received, send a proactive message to the user to either 1) see if they're still there, or 2) end the conversation.