Thanks — that’s a great question, and I understand the frustration with blank calls. I’m responding to your question about when to create the SIP participant and how to avoid the agent immediately ending the call. Short answer • Create the SIP participant before calling

session.start()

. • Preferably create it with a wait option (e.g.,

wait_until_answered=True

) or otherwise wait until the participant has joined before letting the agent begin speaking or running any call-ending logic. Why blank calls happen • If the agent session starts before the SIP participant is present, the agent may detect silence or an idle state and trigger tools (like an

end_call

tool) immediately. That makes the call end before the caller hears anything. Correct sequence (recommended) 1. Create the SIP participant (start the outbound call). 2. Wait for the SIP participant to answer / join the room (either by using a built-in wait flag or by listening for the participant-joined event). 3. Start the agent session with

session.start()

and only then let the agent run conversational logic or generate replies. Practical tips • Use a “wait until answered” option when creating the SIP participant so the API call returns only after the call is answered. • If no wait flag is available, add an explicit listener or polling to confirm the participant joined the room before calling

session.start()

or before the agent runs any automatic tools. • Avoid invoking any call-ending tool automatically on agent startup — require explicit user input or a clear timeout after the participant has been present for some time. • As an added safeguard, you can add a short grace period after join detection before running automated actions so transient race conditions don’t trigger end-call logic. If you’d like, share a short snippet of the relevant code flow (how you call

create_sip_participant

and

session.start()

) and I’ll point out exactly where to change it and suggest the safest implementation for your setup. Sources: Outbound Calling Script | LiveKit Documentation | Agents telephony integration | LiveKit Documentation