What is Auto Outbound Call?
Auto Outbound Call is an automated testing feature where Cekura automatically initiates outbound calls when you run evaluators. Unlike manual outbound testing where you write scripts to handle calls, this feature does everything automatically.How It Works
System Calls Automatically
Cekura uses your voice provider (Vapi, Retell, or ElevenLabs) to initiate calls
Prerequisites
- Outbound mode enabled: Agent’s
inboundmust be set tofalse - Voice provider configured: Valid API key and Assistant ID for your provider (Vapi, Retell, or ElevenLabs)
- Agent
contact_numberset to your outbound caller ID: Cekura validates the caller ID (ANI) of every incoming outbound-test call against the agent’scontact_numberfield. If the provider dials from+15551234567, the agent’scontact_numbermust be exactly+15551234567in E.164 format. Set this in Agent settings or via the Update Agent API. - Evaluators ready: Created evaluators with valid phone numbers
Enabling Auto Outbound Call
Navigate to your Agent settings -> Right sidebar -> Connection -> Select Telephony under VOICE -> Toggle ON Auto Outbound Call.
Ensure your voice provider account has sufficient credits for making calls.
Advanced: Trigger URL Webhook
For advanced use cases, you can configure a Trigger URL to receive webhook notifications instead of automatic calls. This lets you add custom logic before the call is made.When to Use
Use trigger URLs when you need to:- Add validation or business logic before calls
- Schedule calls for specific times
- Integrate with internal systems
- Log or audit call requests
How It Works
Add Trigger URL
In your agent settings, enter your webhook URL in the Trigger URL field (below the Outbound Auto Call toggle).

Webhook Payload
Cekura sends the following JSON payload to your trigger URL:from_number: Your agent’s contact number (the number making the call)to_number: The evaluator’s phone number (where to call)dynamic_variables: Optional test profile data for dynamic prompting
Your webhook endpoint must be publicly accessible (HTTPS), return a 200 or 201 status code, and respond within 30 seconds.
Dial window timing: Each outbound run has a dial window that opens when the run reaches
pending status. The call must be placed before outbound_dial_window_closes_at (default 300 seconds after the window opens). Dials received after the deadline are dropped and the run returns status: timeout. The three dial-window fields (outbound_dial_window_opens_at, outbound_dial_window_seconds, outbound_dial_window_closes_at) are included in run responses so you can track the deadline.Response Format
Your webhook should return:Troubleshooting
Calls Not Starting
Calls Not Starting
Check that Auto Outbound Call is enabled, agent is in Outbound mode, and voice provider credentials are valid.
Calls Placed but Run Times Out (Busy / NoAnswer on Provider Side)
Calls Placed but Run Times Out (Busy / NoAnswer on Provider Side)
The provider dialed but Cekura never picked up. Two possible causes:
- Dialed too late — if the provider dialed after
outbound_dial_window_closes_at(check the run response for this field; default is 300 seconds after the run reachedpending), Cekura dropped the call. This can happen if the trigger URL webhook is slow to respond or if there’s a delay in your call logic. - Caller-ID mismatch — Cekura rejects incoming outbound-test calls whose caller ID doesn’t match a configured
contact_numberon any agent in your project. Open the agent under test and confirm itscontact_numberis set to the exact E.164 number the provider dials from (thefrom_numberin the trigger webhook payload). An empty or mismatchedcontact_numbercauses every outbound attempt to be silently dropped — your provider logs will showBusy/NoAnswer/ no-pickup with no audio and no SIP error explaining why. After correctingcontact_number, trigger a fresh run; the timed-out runs cannot be recovered.
Failed to Initiate Call / Permission Errors
Failed to Initiate Call / Permission Errors
Check API key permissions at your provider’s settings. For ElevenLabs, ensure “Conversational AI” and “Phone Number” permissions are enabled at https://elevenlabs.io/app/settings/api-keys. Verify phone number format is E.164 (+1XXXXXXXXXX).
Webhook Not Working
Webhook Not Working
Verify trigger URL is publicly accessible (HTTPS), returns 200/201 status, and no firewall is blocking requests.
Best Practices
- Monitor credits: Track your provider account balance
- Valid numbers: Use correct phone number format (+1XXXXXXXXXX)
- Secure webhooks: Use HTTPS, validate requests, implement rate limiting
Next Steps
- Learn about manual outbound testing for more control
- Explore load testing capabilities
- Set up custom metrics for your tests