In this guide, we'll show you how to send live calls into Regal directly from your own Twilio account using Twilio's Application Connect feature (<Dial><Application>), and how to attach custom contact data to those calls so Regal can route them and personalize the conversation.

This is for customers who run their own Twilio account (for example, a Flex contact center) and want to hand a live call off to a Regal AI agent, or originate calls from their Twilio numbers that a Regal AI Agent handles.

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Getting your Application SID

To use Application Connect, reach out to your Regal FDE or CSM. They'll give you a Twilio Application SID (it looks like APxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx) to dial.

That SID is all you need from Regal to get started.

Why use Application Connect?

If you are currently on Twilio, Application Connect is usually the optimal way to move a live call to us.

• It works across separate Twilio accounts. Twilio does not support SIP transfers between accounts that aren't owned by the same parent organization. Application Connect is purpose-built for exactly this cross-account hand-off.
• No per-agent or per-use-case phone numbers. Unlike a PSTN transfer (<Dial>+1AGENTNUMBER</Dial>), you don't need to provision and maintain a Regal phone number for every routing path. One Application SID handles all of them. This keeps your telephony costs down and avoids buying and branding duplicate numbers.
• Routing data rides on the call itself. You can attach custom parameters to the call (lead source, priority, agent, opportunity ID, which team should handle it, customer intent, product type, etc.). Regal turns those into task attributes you can route on and reference in your AI agent, with no separate pre-call API request to race against the call.

Application Connect plays the same role for Twilio-to-Twilio customers that SIP plays for everyone else, it's just the cross-account-native way to do it on Twilio.

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More on Twilio's side

For the underlying Twilio behavior, see Twilio's docs on <Dial><Application> and custom parameters.

Key Use Cases

How to configure and dial

In your own Twilio application flow, dial Regal's Application SID with <Dial><Application>. Pass any data you want Regal to receive as <Parameter> elements:

<Response>
  <Dial>
    <Application copyParentTo="true">
      <ApplicationSid>APxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx</ApplicationSid>

      <!-- Reserved parameters (used for call identity) -->
      <Parameter name="ContactPhone" value="[the customer's phone number]"/>
      <Parameter name="RegalVoicePhone" value="[found in your active phone numbers]"/>

      <!-- Your custom parameters (added to the task as applicationConnectParams.*) for e.g. -->
      <Parameter name="Priorty" value="high"/>
      <Parameter name="AgentTeam" value="Appointment Pre-Screen"/>
      <Parameter name="LeadId" value="123456789x00"/>
    </Application>
  </Dial>
</Response>

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Contact Resolution

All dials must include a valid ContactPhone parameter, which will either map to an existing user profile, or create one.

A few notes:

• Replace the ApplicationSid with the one your FDE/CSM gave you.
• We recommend setting copyParentTo="true" so the original call leg's To is preserved.
• You can include as many custom <Parameter> elements as you need.

Reserved parameters

Two parameter names are reserved. Regal uses them to identify the call and does not add them to your task attributes:

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RegalVoicePhone is optional

If you don't send RegalVoicePhone (or send one that's invalid), Regal automatically falls back to your default number, so the call still connects.

Sending a valid one is recommended for cleaner reporting and attribution.

Custom parameters

Every additional parameter is added to the task under applicationConnectParams, with the name preserved exactly as you sent it. For the example above:

{
  "applicationConnectParams": {
    "LeadSource": "Direct",
    "FirstName": "Jane",
    "LastName": "Nicholson",
    "SubscriptionType": "Master"
  }
}

Routing on your parameters

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Application Connect calls skip the IVR

Application Connect calls go straight into your Regal queues so they reach an agent as fast as possible, they do not run through an IVR.

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That means your routing rules must be configured ahead of time.

Routing rules are only evaluated when the task is created; they do not apply retroactively to tasks that already exist.

You reference your parameters differently depending on whether you're writing a task expression or a worker expression.

Task expressions reference the attribute directly:

applicationConnectParams.priority == "high"

applicationConnectParams.agent_team CONTAINS "setup"

If you sent a valid RegalVoicePhone, you can also route on the standard task attribute:

regalVoicePhone == "+18005551212"

Worker expressions reference the task with the task. prefix (to distinguish it from worker.). This lets a single Application Connect rule route dynamically, for example matching the worker's team to the team you sent on the call:

worker.teams HAS task.applicationConnectParams.AgentTeam

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Routing Rules

Routing rules are evaluated from top to bottom. The first rule that matches your task will route it. The syntax is particular, you can refer to this Routing Rule Syntax Guide for the full breakdown.

Using parameters downstream

Once a parameter lands on the task, it flows through the rest of Regal alongside your other call data. Your custom parameters are available in Task-related events sent to your downstream destinations, integrations and data warehouses, common events include:

• Transcription & Recording
• Task Creation & Completion

Referencing parameters in your AI agent

Your Regal AI agent can also read these parameters during the call using dynamic variables. In your agent prompt, reference them with task.applicationConnectParams, for example:

"Hi there! This is Elsa from Circle Bank, am I speaking with {{task.applicationConnectParams.FirstName}}?"

Configure Outbound via External Transfer Phonebook

You can map the same Application Connect attributes dynamically in the external transfer phonebook when transferring out of Regal to another Twilio Account Application:

FAQ