Ahmer
09/12/2025, 2:04 PMChiranjeet Mishra
09/15/2025, 4:54 PMassistantId for your fixed assistant.
- Include assistantOverrides with variableValues to set the personalized data.
Example:
json
{
"assistantId": "your-assistant-id",
"assistantOverrides": {
"variableValues": {
"name": "John",
"accountType": "Premium",
"joinDate": "2021-06-15"
}
},
"customer": {
"number": "+123456789"
},
"phoneNumberId": "your-phone-id"
}
2. Dynamic Variables in Prompts:
- Ensure that prompts in your assistant configuration use dynamic variable syntax like {{name}}.
- For instance, a prompt could be: "Hello, {{name}}! Thank you for being a {{accountType}} member since {{joinDate}}."
3. Send the Request:
- Make an API call to the /call/phone endpoint with the JSON payload.
4. Ensure Server Configuration:
- Check that your server responds within the required time (7.5 seconds).
- Confirm dynamic variable placeholders are correctly set up in your assistant configuration.
For detailed information, you can refer to [personalization with user information documentation](https://docs.vapi.ai/assistants/personalization) and [using dynamic variables](https://docs.vapi.ai/assistants/dynamic-variables).Ahmer
09/19/2025, 1:33 PMChiranjeet Mishra
09/23/2025, 3:24 PMassistantOverrides parameter with variableValues [1](https://docs.vapi.ai/assistants/dynamic-variables). Here's how:
{
"assistantId": "your-assistant-id",
"assistantOverrides": {
"variableValues": {
"name": "John",
"customerId": "12345"
}
},
"customer": {
"number": "+1xxxxxxxxxx"
},
"phoneNumberId": "your-phone-id"
}
You can use these variables in your prompts using double curly braces: {{name}}, {{customerId}}, etc.
2. Using the Same Assistant for Web and Phone: Yes, you can use the same assistant for both web and phone calls! The assistant configuration (prompts, variables, etc.) remains consistent across both channels. You just need to:
3. Set up the assistant in the dashboard
4. Configure it for phone calls by attaching it to a phone number
5. Use the same assistant ID when integrating with your web application
You don't need separate bots - any changes made to the assistant will automatically apply to both web and phone interactions.
Some default variables are also available automatically, like:
- {{now}} - Current date/time
- {{date}} - Current date
- {{customer.number}} - Customer's phone numberAhmer
09/24/2025, 12:27 PMChiranjeet Mishra
09/29/2025, 6:14 PMassistantId on the phone number configuration - this will always use the same assistant
- Leave assistantId blank - Vapi will make an "assistant-request" to your server webhook, where you can dynamically return which assistant to use
2. For setting variables, you would need to:
a) Create an assistant in the Dashboard with dynamic variables like {{name}} in the prompts b) When making a call (outbound) or responding to an assistant-request (inbound), provide the variable values in `assistantOverrides.variableValues`:
{
"assistantOverrides": {
"variableValues": {
"name": "John"
}
}
}
When you receive an assistant-request webhook on your server, you can:
1. Look up customer details based on their phone number
2. Return an assistant response with the appropriate variable values
3. Vapi will then start the call using that assistant with the provided variables