<@U07FRRZH2GN> How does a human in the loop system...
# ask-ai
f
@icy-policeman-64898 How does a human in the loop system work over a phone call, we are suigna third party sip provider
✅ 1
t
Thanks for reaching out, Abhishek. I'm an AI assistant and I'm here to help. Give me a moment while I research this topic.
Thanks — you’re asking how a human-in-the-loop (HITL) flow works over a phone call when you’re using a third‑party SIP provider. I’ll explain the options, the pieces you’ll need, and next questions that help me guide you to an implementation. Summary — two transfer patterns • Warm transfer (agent‑assisted): The AI stays on the call, dials a human via SIP, places the caller on hold, shares conversation context with the human, connects them, then optionally drops off. LiveKit provides a prebuilt WarmTransferTask to automate this workflow. • Cold transfer (call forwarding): The AI instructs the SIP network to forward the call (REFER) directly to the human’s number or SIP endpoint; the AI doesn’t remain on the line. What you need to implement HITL with a third‑party SIP provider • Outbound SIP trunk: usable by LiveKit/agent to dial out to human agents. • Ability to create SIP participants: use the CreateSIPParticipant API to initiate outgoing calls from LiveKit into your SIP provider. • Dispatch / routing rules: logic to decide when to escalate, which human to call, etc. • Conversation context handoff: pass conversation history/metadata to the human (so they see context when answering). • Optional features: hold music for warm transfers, Krisp noise cancellation for better audio quality, monitoring/logging for QA. Supported SIP providers • LiveKit has been used with Twilio, Telnyx, Exotel, Plivo, Wavix — and is designed to work with any third‑party SIP provider that supports standard SIP trunks and REFER for forwarding. Implementation notes & recommended flow 1. Incoming call arrives (via SIP) into LiveKit’s telephony flow or your agent. 2. AI handles conversation; when escalation is needed: ◦ For warm transfer: i. Create an outbound SIP participant to dial the human agent’s number. ii. Place the caller on hold (play hold music). iii. When human answers, surface conversation history/context. iv. Bridge the human and caller; the AI may then drop or stay for monitoring. ◦ For cold transfer: i. Use SIP REFER or your provider’s call transfer API to forward caller to human. ii. AI disconnects immediately (no bridged session). 1. Track call state and logs for analytics and post‑call review. Questions to help me tailor guidance • Which SIP provider are you using (Twilio, Telnyx, etc.)? • Do you want the AI to remain on the call for monitoring (warm) or hand off immediately (cold)? • Do you already have an outbound trunk set up, or do you need steps for configuring one? • Are you using LiveKit Agents SDK (e.g., WarmTransferTask) or building custom logic? If you tell me your SIP provider and whether you prefer warm or cold transfer, I can provide step‑by‑step guidance (example API calls, CreateSIPParticipant usage, or WarmTransferTask setup) and point to the exact docs you’ll need. Sources: Agents telephony integration | LiveKit Documentation | WarmTransferTask | LiveKit Documentation | LiveKit Phone Numbers | Connect voice agents to phone lines | LiveKit, with interactive elements
f
tell em like complete implementstion of warm hand off
t
Thanks — you want a complete implementation guide for a warm handoff (warm transfer) over a phone call using a third‑party SIP provider with LiveKit. I’ll walk you through the full flow, required components, configuration, example code (Python using the LiveKit Agents SDK’s WarmTransferTask), and important best practices. Quick question first: • Do you already have an outbound SIP trunk with your provider and SIP credentials that LiveKit can use? If not, I’ll include provider‑agnostic trunk setup notes you can adapt. Overview — what the warm handoff does • During a call the AI places the caller on hold, dials a human agent via your SIP provider, presents conversation context to the human, connects (bridges) the human and caller, and then optionally drops off. The AI remains on the line until the human joins and the bridge is established. Components you need • LiveKit room handling the active call. • Outbound SIP trunk (with your SIP provider) that LiveKit can use to place outbound calls. • Ability to create a SIP participant in LiveKit (CreateSIPParticipant). • LiveKit Agents SDK support (WarmTransferTask) or equivalent custom logic. • Hold music/media source for the caller while dialing the human. • Mechanism to surface conversation context to the human agent (metadata, web UI, CRM). • Logging/metrics to track transfer success and failures. High-level warm transfer flow 1. Detect escalation need in your AI/agent logic. 2. Place the caller on hold (play hold music into the caller’s audio track). 3. Create an outbound SIP participant that dials the human agent via your SIP trunk. 4. Wait for the human to answer; surface conversation context to them. 5. Once the human is connected, bridge the human’s SIP participant into the caller’s room (connect audio). 6. Optionally, remove the AI participant (disconnect) or remain for monitoring. 7. Log the transfer result and update conversation state. Step‑by‑step implementation (Python, using WarmTransferTask) Below is a conceptual implementation using the WarmTransferTask from the Agents SDK (beta). Adjust variable names, room IDs, and credentials to your environment. 1) Prerequisites • LiveKit server accessible and configured with SIP trunk credentials. • Your SIP provider configured to allow outbound calls from LiveKit (SIP trunk). • Agents SDK installed (Python) and credentials for LiveKit API. • A LiveKit room where the caller is present and your AI agent is connected. 2) Preparing hold music and context • Provide an audio file or stream as hold music. • Ensure you have conversation history text and relevant metadata ready to hand off (transcripts, intent, caller details). 3) Create and run a WarmTransferTask • The WarmTransferTask will: ◦ Create an outbound SIP participant. ◦ Play hold music into the caller’s audio while dialing the human. ◦ Wait for the human to answer, then bridge. Example (conceptual) Python flow:
Copy code
from livekit_agents import WarmTransferTask, AgentsClient

# Initialize client (fill in with your auth)
client = AgentsClient(api_key="LIVEKIT_API_KEY")

# Variables
room_id = "room-1234"            # room with caller and AI agent
caller_participant = "caller-1"
human_phone_number = "+15551234567"
hold_audio_url = "https://example.com/hold-music.mp3"
transfer_metadata = {
    "transcript": "... recent transcript ...",
    "summary": "Caller needs billing assistance; account #12345",
}

# Create the WarmTransferTask
task = WarmTransferTask(
    room_id=room_id,
    from_participant="ai-agent",        # the AI agent participant
    to_sip_number=human_phone_number,
    hold_audio_url=hold_audio_url,
    metadata=transfer_metadata,
    sip_trunk="your-sip-trunk-id"      # identifier configured in LiveKit
)

# Run the task (this will dial the human, play hold to caller, and bridge)
result = client.run_task(task)

if result.success:
    print("Warm transfer completed; human connected.")
else:
    print("Warm transfer failed:", result.error_message)
Notes: • The exact class/method names and parameters might vary with SDK versions; use the SDK docs for exact signatures. •
sip_trunk
represents the outbound trunk configured in LiveKit to reach your SIP provider. Alternative: Manual implementation without WarmTransferTask If you prefer custom control (or the task isn’t available), implement the same steps manually: 1. Place caller on hold ◦ Mute caller’s microphone track if needed and inject hold music audio into the caller’s subscribed track. 1. Create SIP participant ◦ Call LiveKit’s CreateSIPParticipant API with the destination number and trunk details. Example payload fields: ▪︎ `room`: room_id ▪︎ `display_name`: "Human Agent" ▪︎ `sip`: destination URI (e.g., sip:+15551234567@provider.example.com) ▪︎ `trunk`: trunk identifier for outbound routing ▪︎ `metadata`: conversation summary / context 1. Monitor SIP call state ◦ Listen for events: ringing, answered, failed, busy, no-answer. ◦ When answered, confirm audio connectivity. 1. Bridge audio ◦ Once human answers, connect their audio into the caller’s room. Ensure: ▪︎ Caller hears human and human hears caller. ▪︎ AI agent is either muted/disconnected as desired. 1. Tear down / cleanup ◦ If AI disconnects, ensure the room participant state is updated and resources freed. ◦ Log timestamps and results (transfer start, answer, bridge complete). Key API points to use • CreateSIPParticipant: to dial the human via your SIP trunk. • Participant update events: to track answered/connected state. • Room media controls: to play hold music and to connect/disconnect participants. Practical configuration tips • SIP trunk setup: ensure authentication, codecs (e.g., PCMU/PCMA, Opus if supported), and NAT traversal (SRTP, TLS) are configured with your provider. • Hold music: short looped MP3 or an RTP stream; ensure format matches room expectations. • Conversation context delivery: send a webhook or populate a UI with
metadata
so the human sees prior transcript and summary before they pick up. • Timeouts: set sensible timeouts for dialing human (e.g., 25–45s) and fallback behavior (voicemail, callback, route to backup agent). • Retries & fallback: on failure, try alternate agents or escalate to supervisor. • Monitoring: expose transfer events to your monitoring/analytics for QA. • Privacy & compliance: ensure you handle PII/transcripts according to regulations (store minimal data in metadata). Failure modes and recovery • Human doesn’t answer: unbridge, play message to caller, retry another agent, or fall back to voicemail. • SIP trunk failure: detect and attempt alternate trunk or notify system. • Audio mismatch (codec/NAT): ensure supported codecs and ICE/STUN/TURN configuration; monitor for one-way audio and adjust codecs or trunk settings. What I can provide next • Exact example API payloads for CreateSIPParticipant if you tell me your SIP provider. • A full working sample (expanded Python script) wired to your LiveKit API keys and room flow. • Troubleshooting steps for common issues (one‑way audio, registration, REFER support). • UI examples for surfacing conversation context to the human agent. Please tell me: • Which SIP provider you’re using (Twilio, Telnyx, Plivo, etc.), or if you need provider‑agnostic instructions. • Whether you want the AI to drop off after the bridge or stay for monitoring. With that I’ll give you precise API call examples and a complete runnable sample. , with interactive elements