Outbound Calling

Outbound calling lets your voice agent place calls to phone numbers instead of waiting for inbound calls. Your AI dials the number, the recipient picks up, and a natural voice conversation begins — powered by the same system prompt, knowledge base, and tools as your inbound voice agent.

How It Works

Outbound calls use SIP (Session Initiation Protocol) through LiveKit to place real phone calls. When you trigger an outbound call:

1. Chipp creates a voice room and dials the recipient via your SIP trunk
2. The recipient’s phone rings with your configured caller ID
3. When they answer, your voice agent joins the call and begins the conversation
4. The agent uses the same voice, greeting, system prompt, and tools as inbound calls
5. The call is recorded as a chat session you can review in Insights → Conversations

Each call has a configurable maximum duration (default 10 minutes, up to 60 minutes).

Inbound vs. Outbound

Placing Calls from the Builder

Go to Experience → Phone and open the Outbound Calls section:

• Make a Test Call: dial a single number to test your voice agent
• Create Campaign: batch call a list of recipients via CSV or manual entry

The same section lists your campaigns and their progress. The endpoints below are what the builder uses under the hood.

Single Outbound Call

To place a single outbound call, use the endpoint:

POST /api/applications/:id/voice/outbound-call

{
  "phoneNumber": "+15551234567",
  "callerIdName": "Acme Support",
  "maxDurationSeconds": 300,
  "metadata": {
    "recipientName": "Jane Smith",
    "reason": "appointment-reminder"
  }
}

The response includes a callId, roomName, chatSessionId, and sipCallId you can use for tracking.

Batch Calling

For calling multiple recipients, use the batch endpoint:

POST /api/applications/:id/voice/outbound-batch

{
  "recipients": [
    { "phoneNumber": "+15551234567", "metadata": { "name": "Jane" } },
    { "phoneNumber": "+15559876543", "metadata": { "name": "Mike" } }
  ],
  "callerIdName": "Acme Reminders",
  "callsPerMinute": 5
}

Small batches (10 or fewer recipients) are placed immediately with a short delay between each call. Larger batches create a campaign that processes calls in a managed queue.

Campaigns (CSV Upload)

For large-scale outreach, upload a CSV file of recipients:

POST /api/applications/:id/voice/outbound-campaign

{
  "csvContent": "phone,name,appointment_date\n+15551234567,Jane Smith,2026-04-01\n+15559876543,Mike Jones,2026-04-02",
  "callerIdName": "Acme Scheduling",
  "callsPerMinute": 10
}

CSV Format

Your CSV must include a header row with a phone number column. Accepted column names:

• phone
• phonenumber
• phone_number
• number

All other columns are attached as metadata to each call, so the AI has context about who it is calling.

Example CSV:

phone,name,appointment_date,location
+15551234567,Jane Smith,2026-04-01,Downtown Office
+15559876543,Mike Jones,2026-04-02,Midtown Clinic

Campaign Status

Campaigns track progress through these statuses:

Each recipient is independently tracked as pending, queued, calling, completed, failed, or no-answer.

List your campaigns:

GET /api/applications/:id/voice/campaigns?limit=50&offset=0

Phone Number Format

Phone numbers are normalized to E.164 format before dialing. Numbers without a country code use the country of your app’s phone number (US if none):

• (555) 123-4567 becomes +15551234567 (for a US number)
• 1-555-123-4567 becomes +15551234567
• +44 20 7946 0958 stays as-is (international)

Numbers must be between 10 and 15 digits. Invalid numbers are rejected before the call is placed.

Use Cases

Best Practices

System Prompt for Outbound

Add outbound-specific instructions to your system prompt:

When making an outbound call:
- Introduce yourself and state the reason for calling immediately
- If you reach voicemail, leave a brief message with a callback number
- Be respectful of the recipient's time -- keep calls concise
- If asked, explain that this is an AI-powered call from [Company Name]

Rate Limiting

Start with a low callsPerMinute (3—5) and increase gradually. High call volumes may be flagged by carriers.

Metadata for Context

Pass recipient-specific data in the metadata field. The AI can reference this context during the conversation — for example, the recipient’s name, appointment date, or account status.

Troubleshooting

Calls not connecting?

• Verify voice mode is enabled and a phone number is assigned
• Check that the recipient’s phone number is valid E.164 format
• Ensure your SIP outbound trunk is configured (contact support if unsure)

Recipient hears nothing?

• Check your voice agent’s greeting configuration
• Verify the voice selection is set (stock or cloned voice)
• Review call records in Insights → Conversations for errors

Campaign stuck in “pending”?

• Large campaigns are processed asynchronously — allow time for the queue to start
• Check that your plan supports outbound calling