ElevenLabs integration (API)

This guide shows how to integrate ElevenLabs with Vobiz programmatically to enable outbound calling and automate voice calls with ultra-realistic AI voices.

Prefer using the dashboard? Check out the dashboard setup guide for a visual step-by-step walkthrough.

Perfect for:

Application integration
Bulk calling campaigns
Automation workflows
Custom call triggers

Call flow: Your App → ElevenLabs API → Vobiz SIP → Phone Network → Person Answers → AI Agent Speaks

Prerequisites

Vobiz account with SIP trunk → Create account
ElevenLabs account with API key → Sign up
ElevenLabs API key → Get API key
Phone number from Vobiz (for caller ID)

Part 1: Vobiz setup

Create a SIP trunk

Create a SIP trunk in Vobiz to handle voice traffic. See: Vobiz SIP trunks documentation Save these values from the response:

sip_domain (for example, abc123def.sip.vobiz.ai)
username
password

You’ll need them for ElevenLabs configuration.

Get a phone number

Purchase a phone number for outbound caller ID. See: Vobiz phone numbers documentation

Part 2: ElevenLabs setup

Step 1: Get your API key

Via dashboard:

Go to ElevenLabs Developer → API Keys
Click Create API Key
Name your key (for example, “Vobiz Integration”)
Set permissions:
- ElevenLabs Agents: Write (Required)
- Voices: Read (Required)
- User: Read (Optional)
Click Create and copy the key

sk_your_elevenlabs_api_key_here

Save this key securely - you’ll use it in all API requests.

Step 2: List available voices

curl "https://api.elevenlabs.io/v1/voices" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here"

What to extract:

voice_id - use this when creating your agent
name - voice name for identification
category - voice type (premade, cloned, etc.)

{
  "voices": [
    {
      "voice_id": "voice_id_here",
      "name": "Rachel",
      "category": "premade",
      "labels": {
        "accent": "american",
        "age": "young"
      }
    },
    {
      "voice_id": "another_voice_id",
      "name": "Domi",
      "category": "premade"
    }
  ]
}

Copy a voice_id - you’ll need it in Step 3.

Step 3: Create an agent

curl -X POST "https://api.elevenlabs.io/v1/convai/agents" \
  -H "Content-Type: application/json" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here" \
  -d '{
    "name": "Customer Support Bot",
    "conversation_config": {
      "agent": {
        "prompt": {
          "prompt": "You are a helpful customer support assistant. Be friendly, professional, and concise."
        },
        "first_message": "Hello! Thank you for calling. How can I help you today?",
        "language": "en"
      },
      "tts": {
        "voice_id": "voice_id_here"
      }
    }
  }'

Replace:

voice_id_here → your chosen voice ID from Step 2

{
  "agent_id": "agent_your_agent_id_here",
  "name": "Customer Support Bot",
  "conversation_config": {
    "agent": {
      "first_message": "Hello! Thank you for calling. How can I help you today?",
      "language": "en"
    }
  }
}

Save the agent_id - you’ll need it to make calls.

Part 3: Connect Vobiz to ElevenLabs

Step 1: Import your phone number

curl -X POST "https://api.elevenlabs.io/v1/convai/phone-numbers" \
  -H "Content-Type: application/json" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here" \
  -d '{
    "provider": "sip_trunk",
    "phone_number": "+911234567890",
    "label": "Vobiz Main Line",
    "inbound_trunk_config": {},
    "outbound_trunk_config": {
      "address": "abc123def.sip.vobiz.ai",
      "transport": "tcp",
      "credentials": {
        "username": "your_username",
        "password": "your_password"
      }
    },
    "supports_inbound": true,
    "supports_outbound": true
  }'

Replace:

+911234567890 → your Vobiz phone number
abc123def.sip.vobiz.ai → your Vobiz SIP domain
your_username → your Vobiz username
your_password → your Vobiz password

{
  "phone_number_id": "phnum_your_phone_number_id_here",
  "phone_number": "+911234567890",
  "label": "Vobiz Main Line",
  "supports_outbound": true,
  "supports_inbound": true,
  "provider": "sip_trunk"
}

Save the phone_number_id - you’ll need it in Step 2. Get Vobiz credentials:

Via console: Vobiz Console → Trunks
Via API: Vobiz API reference

Step 2: Make an outbound call

curl -X POST "https://api.elevenlabs.io/v1/convai/sip-trunk/outbound-call" \
  -H "Content-Type: application/json" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here" \
  -d '{
    "agent_id": "agent_your_agent_id_here",
    "agent_phone_number_id": "phnum_your_phone_number_id_here",
    "to_number": "+919988776655"
  }'

Replace:

agent_your_agent_id_here → your agent ID from Part 2, Step 3
phnum_your_phone_number_id_here → your phone number ID from Step 1
+919988776655 → destination number to call

{
  "success": true,
  "message": "Outbound call initiated",
  "conversation_id": "conv_your_conversation_id_here",
  "sip_call_id": "SCL_your_sip_call_id"
}

Call initiated. What happens next:

The phone rings at the destination
When answered, the agent speaks
The conversation begins with a natural voice

Verification

List your agents

curl "https://api.elevenlabs.io/v1/convai/agents" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here"

[
  {
    "agent_id": "agent_your_agent_id_here",
    "name": "Customer Support Bot",
    "conversation_config": {
      "agent": {
        "first_message": "Hello! How can I help you today?",
        "language": "en"
      }
    }
  }
]

Check call logs

View your call history in ElevenLabs Dashboard → Call History. Test call flow:

Run Step 2 to initiate a call.
Wait for the destination phone to ring.
Answer the call.
The AI agent will greet and speak.
Check the call transcript in the ElevenLabs Dashboard.

Troubleshooting

”Unauthorized” / 401 error

Problem: ElevenLabs API key is invalid or expired. Fix:

Verify you copied the entire key (starts with sk_).
Check the API key has ElevenLabs Agents: Write permission.
Generate a new key at ElevenLabs Developer.

”Not Found” / 404 error

Problem: Agent ID or phone number ID doesn’t exist. Fix:

List your agents to verify the agent ID is correct.
Check the phone number is configured in ElevenLabs Dashboard.
Ensure you’re using the correct ID format.

SIP 408 request timeout

Problem: The Vobiz trunk cannot reach ElevenLabs SIP servers. Fix:

Verify the Vobiz trunk configuration in Vobiz Console.
Ensure transport is set to tcp.
Check the trunk status is active.
See: Vobiz SIP trunks guide.

”Insufficient balance”

Problem: Vobiz account has no credits. Fix:

Call connects but silent

Problem: Agent configuration issue or voice not set. Fix:

Verify the agent has first_message configured.
Check the agent has a valid voice_id in conversation_config.
Test the voice in the ElevenLabs dashboard first.
View call logs in ElevenLabs Dashboard.

Call doesn’t connect

Problem: Wrong phone number format or trunk configuration. Fix:

Use E.164 format: +919988776655 (with + and country code).
Verify the Vobiz trunk is active.
Check Vobiz CDR logs for call attempts at Vobiz Console.
Ensure the phone number is not blocked.

Quick reference

Required credentials

Credential	Where to get	Example
ElevenLabs API Key	ElevenLabs Developer → API Keys	`sk_your_elevenlabs_api_key_here`
Voice ID	Part 2, step 2 (List Voices)	`voice_id_here`
Agent ID	Part 2, step 3 (Create Agent)	`agent_your_agent_id_here`
Phone Number ID	Part 3, step 1 (Import Phone)	`phnum_your_phone_number_id_here`
Vobiz SIP Domain	Vobiz Console → Trunks	`abc123def.sip.vobiz.ai`
Vobiz Username	Vobiz Console → Trunks	`your_username`
Vobiz Password	Vobiz Console → Trunks	`your_password`

API endpoints

Base URL: https://api.elevenlabs.io - all requests require xi-api-key: YOUR_ELEVENLABS_API_KEY

Action	Method	Endpoint
List voices	GET	`/v1/voices`
Create agent	POST	`/v1/convai/agents`
List agents	GET	`/v1/convai/agents`
Import phone number	POST	`/v1/convai/phone-numbers`
Make outbound call	POST	`/v1/convai/sip-trunk/outbound-call`

Common errors

Error	Cause	Fix
401 Unauthorized	Wrong API key	Regenerate at ElevenLabs Developer
404 Not Found	Wrong agent or phone ID	List agents to verify IDs
408 SIP timeout	Trunk config wrong	Check Vobiz Console → Trunks
Insufficient balance	Low Vobiz credits	Add funds in Vobiz Console

Complete example

Here’s a complete working example with real values:

# 1. List voices
curl "https://api.elevenlabs.io/v1/voices" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here"
# Save a voice_id from the response

# 2. Create the agent
curl -X POST "https://api.elevenlabs.io/v1/convai/agents" \
  -H "Content-Type: application/json" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here" \
  -d '{
    "name": "Customer Support Bot",
    "conversation_config": {
      "agent": {
        "prompt": { "prompt": "You are a helpful customer support assistant." },
        "first_message": "Hello! How can I help you today?",
        "language": "en"
      },
      "tts": { "voice_id": "voice_id_here" }
    }
  }'
# Response: save agent_id

# 3. Import the phone number
curl -X POST "https://api.elevenlabs.io/v1/convai/phone-numbers" \
  -H "Content-Type: application/json" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here" \
  -d '{
    "provider": "sip_trunk",
    "phone_number": "+911234567890",
    "label": "Vobiz Main Line",
    "inbound_trunk_config": {},
    "outbound_trunk_config": {
      "address": "abc123def.sip.vobiz.ai",
      "transport": "tcp",
      "credentials": { "username": "your_username", "password": "your_password" }
    },
    "supports_inbound": true,
    "supports_outbound": true
  }'
# Response: save phone_number_id

# 4. Make a call
curl -X POST "https://api.elevenlabs.io/v1/convai/sip-trunk/outbound-call" \
  -H "Content-Type: application/json" \
  -H "xi-api-key: sk_your_elevenlabs_api_key_here" \
  -d '{
    "agent_id": "agent_your_agent_id_here",
    "agent_phone_number_id": "phnum_your_phone_number_id_here",
    "to_number": "+919988776655"
  }'
# Response: call initiated

ElevenLabs integration (API)

Prerequisites

Part 1: Vobiz setup

Part 2: ElevenLabs setup

Part 3: Connect Vobiz to ElevenLabs

Verification

Troubleshooting

Quick reference

Complete example

Resources

Vobiz documentation

ElevenLabs documentation

​Prerequisites

​Part 1: Vobiz setup

​Part 2: ElevenLabs setup

​Part 3: Connect Vobiz to ElevenLabs

​Verification

​Troubleshooting

​Quick reference

​Complete example

​Resources

Vobiz documentation

ElevenLabs documentation

Prerequisites

Part 1: Vobiz setup

Part 2: ElevenLabs setup

Part 3: Connect Vobiz to ElevenLabs

Verification

Troubleshooting

Quick reference

Complete example

Resources