Buttons
Buttons are a way to let users respond to the chatbot in an unambiguous manner. You can add buttons to text, gallery, and list cards. Buttons have a label and a payload. The label is what the user gets to see. Payload is what happens in the backend when the user clicks the button:
A button can take one of four types of payloads: next block, URL, phone number, or share. The next block is identified by the name of the block. This will tell the chatbot which block to execute when the button is pressed. The URL can be specified, if the chatbot is to open a web page on the embedded web browser. Since the browser is embedded, the size of the window can also be specified. The phone number can be specified, if the chatbot is to make a voice call to someone (for example, call to reserve a table). And finally, the Share option can be used in cards such as lists and galleries to share the card with other contacts of the user.