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Contact centers

Send calls from Amazon Connect, Five9, Genesys Cloud, Talkdesk, Twilio, Microsoft Dynamics 365, NICE CXone or Zoom Contact Center to a ThunderPhone agent over SIP, and get them back with the agent

A ThunderPhone agent can answer calls inside your contact center's call flow. Your platform sends the call to the agent's SIP address with SIP headers that carry its own call id and anything else it knows about the caller. When the caller needs a person, the agent hands the call back with a hand-off: a summary of what the caller needs, a short intent label and an id your flow can look up.

Platforms

Platform	How the call arrives	Call-id header	How it comes back	How the context gets back
Amazon Connect	External voice transfer connector; IP allowlist	`X-Amzn-ConnectContactId`	Return: the agent hangs up and the flow resumes	A Lambda calls the hand-off lookup
Five9	AI Agent Connect, set up by Five9, to a dial-in number; IP allowlist	`X-CallID`	Return: the agent hangs up with routing headers on the `BYE`	`X-Route*` and `X-CustomMetaData` headers into IVR call variables
Genesys Cloud	BYOC Cloud trunk; digest	`x-inin-cnv`	`REFER`, accepted by Take Back and Transfer	Hex UUI inside the transfer address, then a data action
Talkdesk	Connect to Autopilot Voice; IP allowlist	`X-Talkdesk-Interaction-Id`	`REFER` to Talkdesk's escalation address	Hex UUI inside the transfer address, then Execute Action
Twilio	`<Dial><Sip>`; digest	`X-Call-ID`, which you add	`REFER` to your `referUrl` handler	Headers inside the transfer address (`ReferTransferTarget`)
Microsoft Dynamics 365	Transfer to a phone number, through your SBC; digest	`X-Call-ID`, which you add	Return, then your SBC routes the caller back	HTTP Request node calls the hand-off lookup
NICE CXone	Studio `Placecall` with `Sipputheader`, to a dial-in number; IP allowlist	`X-Call-ID`, which you add	Return: the agent hangs up (confirm with NICE how the script takes the caller back)	REST API action calls the hand-off lookup
Zoom Contact Center	Bot widget on a trunk Zoom builds, to a dial-in number; IP allowlist with SRTP	`X-ZOOM-Call-Sid`	`REFER` to Zoom's human-agent address	HTTP Call widget calls the hand-off lookup

How it works

Create a SIP endpoint for the agent. Platforms that can answer a password challenge use the endpoint's username and password. Platforms that identify themselves only by their source addresses use an endpoint with auth set to ip_allowlist; see Platforms that authenticate by source IP. Platforms that dial a phone number rather than a SIP address reach the endpoint through its dial-in numbers.
Send calls with context. The platform dials the endpoint's sip_uri or a dial-in number. Every X- header and User-to-User it sends becomes a {{sip_…}} call variable the prompt can use, and its call-id header is stored as the call's external_call_id. See Pass call context in SIP headers.
Add one transfer number that hands the call back, either a SIP address on your platform (the agent sends a REFER) or a return (the agent hangs up and your flow carries on). Its headers can carry {{handoff_summary}}, {{handoff_intent}} and {{handoff_id}}; see Pass context to your contact center.
Read the hand-off where your platform puts it, or look it up by your platform's call id.

Add the transfer number

SIP addresses, returns and their headers are set with the Agents API. A write replaces the whole list, so include the agent's other transfer numbers, then deploy:

curl -X PATCH https://api.thunderphone.com/v1/agents/12 \
  -H "Authorization: Bearer sk_live_YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"transfer_destinations": [{"name": "Contact center", "action": "return"}]}'
 
curl -X POST https://api.thunderphone.com/v1/agents/12/deploy \
  -H "Authorization: Bearer sk_live_YOUR_API_KEY"

Then tell the agent when to use it, by name, in its prompt: "When the caller asks for a person, or you can't resolve the request, transfer to Contact center."

Look up the hand-off

Your flow can fetch the hand-off with your organization's API key and your platform's call id:

curl "https://api.thunderphone.com/v1/calls/handoff?external_call_id=YOUR_PLATFORM_CALL_ID" \
  -H "Authorization: Bearer sk_live_YOUR_API_KEY"

The response has handoff.summary, handoff.intent and handoff.handoff_id, the SIP headers and variables the call started with and, once the call has ended, its summary and extracted data. You can also look a call up by handoff_id. See Look up a handed-off call.

Keep the API key in your platform's credential store, not in the flow itself.