Phone Call Trigger

Description

Use Phone Call Trigger to start a telephone-based conversational workflow when an incoming call is received through the configured telephony provider. Place the trigger at the beginning of the workflow and connect it to a Conversational Agent to let callers interact with the agent using speech.

The trigger configures the incoming telephone connection, the opening greeting, and the ringing duration. The Conversational Agent configures the AI model, instructions, speech recognition, and spoken responses.

Prerequisites

Before configuring the trigger, prepare:

• A telephony account and a phone number enabled to receive voice calls. Use Vobiz, the currently supported provider. See Vobiz Connection and Configure a Vobiz Account.
• A connection for the telephony provider in IB-X. See Connections for creating and managing connections.
• Access to the provider's incoming-call routing settings to configure the webhook for the phone number.
• An IB-X webhook endpoint reachable by the provider.
• A Conversational Agent with an AI model connection, Voice Configuration, and Transcriber Configuration.

Configure the trigger

1. Add Phone Call Trigger to the beginning of the workflow.
2. Double-click the activity to open When phone call received.
3. Configure the Connection, Greetings, and Ringing tabs described below.
4. Click OK to save the activity configuration, or Cancel to discard changes in the dialog.
5. Connect the trigger to the Conversational Agent and configure the agent's model, instructions, voice, and transcriber.

Connection

Property	Description
Telephony Provider	Select the provider that handles incoming telephone calls. Select Vobiz, the currently supported provider.
Connection	Select the connection for the provider account that owns the incoming phone number. Use the + button beside the field to add a connection if needed.
Phone Number	Specify the provider phone number callers will dial to reach this workflow. Use the same number when configuring incoming-call routing in the provider console.
Voice Webhook URL	The incoming-call endpoint to use for the deployed agent. Copy the URL using the copy icon beside the field.
Debug Webhook URL	The endpoint to use when testing the agent from the designer. Copy the URL using the copy icon beside the field.

Configure incoming-call routing in Vobiz

Vobiz routes incoming calls through a Voice XML Application assigned to the phone number.

1. Sign in to the Vobiz Console with the account used by the selected connection.
2. Create or open the application for this workflow in Voice / XML Applications.
3. Set Answer URL to the trigger endpoint: Debug Webhook URL for testing or Voice Webhook URL for the deployed agent.
4. Save the application and assign the incoming phone number to it.
5. Call the number and verify that the intended workflow receives the call.

See Configure a Vobiz Account for account and number preparation.

important

Copy the full URL from your own activity configuration. Switch the Vobiz application Answer URL when moving between debugging and deployment. Use a dedicated application to avoid changing routing for other numbers.

Greetings

Property	Description
First Message	Controls who begins the conversation. Select Agent speaks first to have the agent open the call with the configured greeting.
Greeting Message	The opening text spoken by the agent when Agent speaks first is selected. This field is marked as required in the configuration shown.

For example:

Hi, How may I assist you today?

Write a short greeting that identifies the service and invites the caller to explain their request. For a support workflow, you could use:

Hello, you've reached the support assistant. How can I help you today?

The greeting establishes the opening of the call. Configure the agent's ongoing behavior separately in its Agent Persona and Instructions, and select the spoken voice in Voice Configuration.

Ringing

Property	Description	Range	Example
Minimum Ring (seconds)	Sets the lower bound for the ringing duration before the call is answered.	0–10 seconds	2 seconds
Maximum Ring (seconds)	Sets the upper bound for the ringing duration before the call is answered.	0–10 seconds	6 seconds

Adjust the sliders to choose the ringing bounds. Keep Minimum Ring less than or equal to Maximum Ring. These are illustrative values, rather than documented defaults.

With a minimum of 2 seconds and a maximum of 6 seconds, the configured ringing window is 2–6 seconds. These settings control the opening ring period; they do not set the length of the conversation or the time the agent waits for a caller to speak. Configure idle prompts and automatic conversation ending in the Conversational Agent's Inactivity & Session Settings.

Example: Telephone support assistant

Build the workflow with this structure:

Incoming caller → Vobiz phone number → Phone Call Trigger → Conversational Agent

1. In Connection, select Vobiz, select the corresponding connection, and specify the incoming phone number.
2. In Greetings, select Agent speaks first and enter the support greeting.
3. In Ringing, set the minimum to 2 seconds and the maximum to 6 seconds.
4. In the Conversational Agent, configure the support instructions, AI model, text-to-speech voice, and speech-to-text transcriber. Add any tools needed to handle requests.
5. Configure the Vobiz application Answer URL with the trigger's Debug Webhook URL and start the designer's debugging session.
6. Call the number. Check that the call reaches the workflow, the greeting is audible, the caller's speech is recognized, and the agent responds appropriately.
7. Deploy the configured agent and switch the Vobiz application Answer URL to the Voice Webhook URL. Make another test call to verify the deployed workflow.

For a broader walkthrough of the agent configuration, see Building a Conversational Agent.

Troubleshooting

Symptom	What to check
Calling the number does not start the workflow.	Confirm the provider account and phone number match the selected connection. Check that the number supports incoming voice calls and that its assigned XML Application Answer URL points to the full URL copied from this trigger. Verify that the provider can reach the IB-X endpoint.
A call does not reach the designer while testing.	Check that the provider is using the Debug Webhook URL and that the intended designer debugging session is active.
Calls stop reaching the deployed agent after testing.	Restore the Voice Webhook URL in the Vobiz application Answer URL and verify the agent is deployed.
The agent does not deliver the expected greeting.	Check First Message, the Greeting Message, and the Conversational Agent's text-to-speech connection and voice configuration.
The agent cannot understand the caller or its responses are inaudible.	Check the Conversational Agent's transcriber language, speech-to-text connection, text-to-speech connection, and voice configuration.
The ringing delay is unsuitable.	Review both ringing bounds and test the caller experience with a real call.

Related pages

• Conversational Agent — Configure conversation behavior, AI models, voice, transcription, and tools.
• Connections — Create and manage provider connections.
• Voice Capabilities — Understand speech recognition and spoken responses.
• Advanced Voice Configuration — Tune listening and interruption behavior.
• Conversational Agent Best Practices — Design and test effective conversations.