In this guide, you will learn how to automatically trigger a CloudTalk VoiceAgent call from Zoho CRM using Workflow Rules.

User level: Admin

Before you start

You will need:

A CloudTalk VoiceAgent already created (note the VoiceAgent ID)
CloudTalk API credentials (API Key and Secret) found in Company Settings > Integrations > API (How to access and generate your CloudTalk API keys)
Zoho CRM Professional plan or above
A phone field available on Contact or Lead records

Generate the Authorization header

CloudTalk uses Basic Authentication for API requests.

Open https://www.debugbear.com/basic-auth-header-generator
Enter your CloudTalk API Key as Username and your API Secret as Password
Copy the generated value. It looks like: Basic XXXXXXXXX

Set up the integration

Create the Webhook

1. In Zoho CRM, click the Gear icon in the top right corner, then go to Automation > Actions > Webhooks

2. Click Configure Webhook

3. Fill in the webhook details:

Field	Value
Name	CloudTalk VoiceAgent
URL to Notify	`https://api.cloudtalk.io/v1/voice-agent/calls`
Method	POST
Authorization Type	General
Module	Contacts or Leads

4. Under Custom Headers, add:

Authorization → Basic XXXXXXXXX (your generated value)
Content-Type → application/json

5. Under Body, set Type to Raw and Format to JSON, then paste:

{
  "call_number": "${Contacts.Phone}",
  "voice_agent_id": "YOUR_VOICE_AGENT_ID"
}

call_number and voice_agent_id are the only mandatory fields. You can also pass optional call_properties such as system prompt variables and output variables, depending on your VoiceAgent configuration. Learn what to include

6. Click Save

Create the Workflow Rule

1. Click the Gear icon in the top right corner, then go to Automation > Workflow Rules

2. Click Create Rule

Note: Webhooks are available from Zoho CRM Professional edition and above.

3. Configure the rule:

Select the module (e.g. Contacts or Leads) and give the rule a name
Set the trigger (e.g. a record is created, a field is modified)
Add conditions to filter records (e.g. phone field is not empty)
Under Instant Actions, add: Webhook > CloudTalk VoiceAgent

4. Click Save and then Activate the rule

Test and verify

Create or update a Contact that meets your trigger conditions
Go to Gear icon > Automation > Workflow Rules, select your rule, and click View Usage to check execution
Verify in CloudTalk that the VoiceAgent call was initiated

You're all set! 🚀 Your Zoho CRM workflow will now trigger a CloudTalk VoiceAgent call whenever a record meets your chosen conditions.

💡 API Limits to Keep in Mind

To avoid failures or throttling, make sure your workflow handles call distribution carefully. Use delays or scheduling logic where needed, as the standard API rate limit (60 requests per minute) applies to the VoiceAgent endpoint.

Troubleshooting

If the VoiceAgent call was not made, go to View Usage and click Failures. Find your record and check the Reason For Failures column.

Error	What to check
Authorization	Incorrect CloudTalk API credentials in the webhook — regenerate and re-enter them
Phone format	Ensure the number is in E.164 format (`+1234567890`)
Incorrect VoiceAgent ID	Verify the `voice_agent_id` in the webhook body is correct
Webhook not triggered	Check that the workflow rule is active and its conditions were met