In this article, you'll learn how VoiceAgent Tools enable real-time actions during live calls by allowing your VoiceAgent to interact directly with external systems via API.
By leveraging Tools, you can turn your VoiceAgent into a fully capable problem-solver, enhancing automation and delivering faster, smarter customer experiences.
User Level:
Admin
What Are Tools?
Tools allow your VoiceAgent to perform specific actions during a call by making API requests to third-party systems. You can configure exactly what each tool does and when it should be triggered based on the conversation.
For example:
A customer asks, “Where’s my order?” → VoiceAgent uses a tool to fetch the latest tracking info.
A patient says, “Can I move my appointment to Friday?” → VoiceAgent calls your booking API to check availability and reschedule.
Other example use cases:
Fetch data:
Look up support ticket details
Access live pricing or availability info
Execute actions:
Update a CRM contact
Trigger a refund
How to Create a Tool
To get started, go to Dashboard > VoiceAgents > Tool Management, then either click the ➕ button in the top-right corner or select Create a Tool to open the configuration panel where you can define how your new tool works.
Here’s how to configure each part:
Tool Fields Reference
Field | Description |
Tool Name | A clear, descriptive name that helps the VoiceAgent decide when to use this tool. Use names like |
Tool Description | Describe in natural language what the tool does and when it should be used. This helps the AI understand in which situations to trigger the tool. |
Awaiting Response Message | A short message the VoiceAgent plays while waiting for the API response. This helps manage silence during execution. |
Method and Endpoint | The HTTP method and API endpoint the tool will call. For example: |
Headers | Define any headers required by the API. These are usually constants like |
Path Parameters | Used to fill in dynamic values within the endpoint URL (e.g., |
Body Parameters | Available for |
Understanding Parameters
When defining a tool, parameters help the VoiceAgent pass the right values to your API. There are three main types of parameters you can use in both path and body definitions:
Parameter Types
Type | Description |
Constant | A fixed value that stays the same for every API call. Useful when you know the exact value you want to send every time. |
Parameter | A dynamic value sent from your system prompt. You’ll reference a variable name here that should match the one sent in your triggering API request. |
LLM Prompt | A natural language instruction to the AI on how to extract a value from the conversation. Best when the input depends on what the caller says. |
Path Parameters
These are values placed directly in the URL. You define them using curly brackets inside the endpoint URL, like {{customer_id}}.
Here’s how it works in practice:
Example Endpoint:
https://api.acme.com/{{customer_id}}/orders
In this case, the customer_id becomes a path parameter.
If defined as a Parameter:
Parameter | Value Source |
|
|
Triggering Request Example:
{
"call_number": "++44123123123",
"voice_agent_id": "6819f0e147851f618cd6aed6",
"call_properties": {
"system_prompt": {
"variables": {
"customer_identifier": "abc123",
}
}
}
}
This results in a call to:
https://api.acme.com/abc123/orders
To extract via LLM Prompt:
Use a clear instruction like:
“Extract the customer ID mentioned by the caller if they provide it. If they don't provide it proactively, ask for it.”
Body Parameters
For POST, PUT, and PATCH methods, you may need to send a request body. These work the same way as path parameters and can also use constants, system prompt variables, or LLM prompts.
Nested objects can be defined using dot notation.
Example Definition:
Parameter | Type | Value |
| Parameter |
|
| LLM Prompt | “Extract the customer’s email address from the conversation.” |
Triggering Request:
{
"call_number": "++44123123123",
"voice_agent_id": "6819f0e147851f618cd6aed6",
"call_properties": {
"system_prompt": {
"variables": {
"customer_identifier": "abc123",
}
}
}
}
This request will result in the following body:
{
"customer_id": "abc123",
"attendee":{
"email":"[email protected]"
}
}
Assigning Tools to VoiceAgents
Tools allow VoiceAgents to perform specific actions during a call, such as triggering external workflows, sending data to other systems, or ending the call. A single VoiceAgent can use multiple Tools, and the same Tool can be used across multiple VoiceAgents.
Tools are triggered as actions within a VoiceAgent Scenario. This means the VoiceAgent will use a Tool only when the situation defined in the Scenario occurs during the call.
To use tool within scenario:
Navigate to the Scenarios & Guardrails section of the VoiceAgent configuration.
Create a new Scenario or edit an existing one.
Define the situation in which the Tool should be used.
In the Action field, select Tool Call.
In the Tools dropdown, choose the Tool you want the VoiceAgent to use.
Save the configuration.
Once configured, the VoiceAgent will automatically use the selected Tool when the scenario conditions are met during a call.
Tips for Using Tools Effectively
Use clear and descriptive tool names
Give each tool a name that clearly reflects what it does. Avoid abbreviations or internal codes.Good:
trigger_refund,get_order_status,book_appointmentNot great:
rfnd_tool_v1,statusQ,app_sched_new
Write a natural language description
In the Tool Description field, explain when and why the VoiceAgent should use the tool. For complex tools, add a short description for each argument the agent needs to collect.
If you need further assistance or have any questions, please submit a request through our Support portal. Our team will be happy to help.