Setting the file. One moment.
Subchapter 1.4
references/outbound-calls.mdMarkdown7 KBView on GitHub
Make outbound phone calls using your ElevenLabs agent via Twilio or Exotel integration.
agent_phone_number_id from the ElevenLabs dashboard)See the main agents skill for basic Twilio Python, JavaScript, and CLI examples.
| Parameter | Type | Provider | Required | Description |
|---|---|---|---|---|
agent_id | string | Twilio, Exotel | Yes | The ID of your ElevenLabs agent |
agent_phone_number_id | string | Twilio, Exotel | Yes | The ID of the linked phone number |
to_number | string | Twilio, Exotel | Yes | The destination phone number in E.164 format |
conversation_initiation_client_data | object | Twilio, Exotel | No | Override conversation settings for this call |
telephony_call_config | object | Twilio, Exotel | No | Telephony call settings like ringing timeout |
call_recording_enabled | boolean | Twilio | No | Whether to let Twilio record the call |
conversation_initiation_client_data also accepts branch_id to route the call to a specific
agent branch and environment to control how environment variables resolve for that call.
{
"success": true,
"message": "Call initiated successfully",
"conversation_id": "conv_abc123",
"callSid": "CA1234567890abcdef"
}| Field | Type | Description |
|---|---|---|
success | boolean | Whether the call was initiated successfully |
message | string | Status message |
conversation_id | string | ElevenLabs conversation ID for tracking |
callSid | string | Provider call SID for reference |
Use the Exotel endpoint when the linked phone number uses the Exotel provider:
elevenlabs agents exotel outbound_call \
--agent-id "your-agent-id" \
--agent-phone-number-id "your-phone-number-id" \
--to-number "+1234567890"Override agent settings for a specific call using conversation_initiation_client_data:
response = client.conversational_ai.twilio.outbound_call(
agent_id="your-agent-id",
agent_phone_number_id="your-phone-number-id",
to_number="+1234567890",
call_recording_enabled=True,
conversation_initiation_client_data={
"branch_id": "branch_support_staging",
"environment": "staging",
"conversation_config_override": {
"agent": {
"first_message": "Hello! This is a reminder about your appointment tomorrow.",
"language": "en"
},
"tts": {
"voice_id": "JBFqnCBsd6RMkjVDRZzb"
}
},
"dynamic_variables": {
"customer_name": "John",
"appointment_time": "2:00 PM"
}
}
)const response = await client.conversationalAi.twilio.outboundCall({
agentId: "your-agent-id",
agentPhoneNumberId: "your-phone-number-id",
toNumber: "+1234567890",
callRecordingEnabled: true,
conversationInitiationClientData: {
branchId: "branch_support_staging",
environment: "staging",
conversationConfigOverride: {
agent: {
firstMessage: "Hello! This is a reminder about your appointment tomorrow.",
language: "en",
},
tts: {
voiceId: "JBFqnCBsd6RMkjVDRZzb",
},
},
dynamicVariables: {
customer_name: "John",
appointment_time: "2:00 PM",
},
},
});| Option | Type | Description |
|---|---|---|
first_message | string | Custom greeting for this call |
language | string | Language code (e.g., “en”, “es”, “fr”) |
prompt | object | Override agent prompt and LLM settings |
| Option | Type | Description |
|---|---|---|
voice_id | string | Voice ID to use for this call |
stability | number | Voice stability (0.0-1.0) |
similarity_boost | number | Voice similarity boost (0.0-1.0) |
speed | number | Speech speed multiplier |
pronunciation_dictionary_locators | array | Pronunciation dictionaries for the call; each locator requires pronunciation_dictionary_id and version_id |
| Option | Type | Description |
|---|---|---|
max_duration_seconds | integer | Maximum duration of this conversation in seconds |
| Option | Type | Description |
|---|---|---|
ringing_timeout_secs | integer | How long to ring the recipient before giving up (default: 60) |
twilio_machine_detection | object or null | Twilio answering-machine detection settings. Omit or set to null to disable. Ignored for non-Twilio providers and inbound calls. |
Set twilio_machine_detection.mode to enable for an early human-or-machine verdict or
detect_message_end to wait for the end of a voicemail greeting. The default is enable.
Detection runs asynchronously. Its verdict arrives through the separate
answering_machine_detection webhook event, which must be enabled in the workspace or agent
webhook settings.
Pass custom data to your agent’s prompt using dynamic_variables. Reference them in your agent’s prompt with {{variable_name}} syntax.
Use branch_id inside conversation_initiation_client_data for per-call branch routing on
Twilio, Exotel, or SIP trunk outbound calls. Use environment alongside it when the call should resolve
workspace environment variables against a non-default deployment target such as staging or
production.
When assigning dynamic variables, you can use the sanitize option to remove sensitive values from tool responses before they are sent to the LLM and transcript, while still allowing variable assignment:
| Field | Type | Default | Description |
|---|---|---|---|
sanitize | boolean | false | If true, the assignment’s value is removed from tool responses before sending to LLM/transcript but still processed for variable assignment |
from elevenlabs import ElevenLabs
client = ElevenLabs()
# Make personalized outbound calls
customers = [
{"name": "Alice", "phone": "+1234567890", "balance": "$150.00"},
{"name": "Bob", "phone": "+0987654321", "balance": "$75.50"},
]
for customer in customers:
try:
response = client.conversational_ai.twilio.outbound_call(
agent_id="payment-reminder-agent",
agent_phone_number_id="your-phone-number-id",
to_number=customer["phone"],
call_recording_enabled=True,
conversation_initiation_client_data={
"conversation_config_override": {
"agent": {
"first_message": f"Hello {customer['name']}, this is a friendly reminder about your account."
}
},
"dynamic_variables": {
"customer_name": customer["name"],
"balance": customer["balance"]
}
}
)
print(f"Called {customer['name']}: {response.conversation_id}")
except Exception as e:
print(f"Failed to call {customer['name']}: {e}")