A developer wants the Copilot Studio agent to display a welcome message and a set of suggested action buttons whenever a new conversation begins — without requiring the user to send a message first. Which system topic handles this behavior?
Select an answer to reveal the explanation.
Short Explanation and Infographic
Conversation Start is the agent's opening handshake — it runs automatically the moment a session begins, perfect for welcome messages and initial menu options before the user says anything. Answer: B.
Full explanation below image
Full Explanation
Copilot Studio includes several system topics that fire based on conversation lifecycle events rather than user utterances.
Option B is correct. The 'Conversation Start' system topic is triggered automatically when a new conversation session is initialized, before the user sends any message. This is where developers add welcome messages, set initial global variables (such as retrieving the user's profile), display an introductory menu of options using Quick Reply buttons or Adaptive Cards, and perform any session setup logic.
Option A is incorrect. While there is a 'Greeting' system topic in some Copilot Studio configurations, standard greeting behavior tied to 'Hello'/'Hi' trigger phrases requires user input. The Conversation Start topic fires without any user input — it is proactive, not reactive.
Option C is incorrect. The Fallback topic fires when the user's input doesn't match any topic — it is reactive and requires user input. It has nothing to do with session initialization or a timeout.
Option D is incorrect. Custom topics always require trigger phrases (or explicit redirects from other topics) to activate. There is no mechanism to designate a custom topic as an automatic session initializer — that is specifically what the Conversation Start system topic provides.