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Functions

Functions extend your voice agent’s capabilities beyond conversation. You can add built-in functions (operator transfer, call ending) or create custom functions that call your own APIs.

Built-in Functions

Operator Transfer

Transfer the caller to a human operator. Two modes are available:
Transfer — Immediately routes the call to the operator’s number. The call is handed off directly without ringing back.

Multiple Transfer Numbers

If you have multiple operator numbers for transfer, list them in the transfer number description field and specify routing conditions. The agent will follow the conditions defined in the prompt to choose the correct number.

Call Ending

Triggers a graceful call termination. The agent delivers a closing message and disconnects.

Call Verification

Validates caller identity or intent before proceeding with the conversation flow.

Custom Functions

Custom functions let your agent call external APIs during a conversation — for example, to look up an order status, check account balance, or create a ticket.

Configuration

FieldDescription
MethodHTTP method for the API call (GET, POST, etc.)
NameA descriptive name for the function
URLThe endpoint URL to call
ParametersInput parameters the agent extracts from the conversation and sends to your API

Using Custom Function Results

Variables returned from custom functions (integrations) are available in the agent’s prompt. Reference them by including usage conditions in your agent’s system prompt.
Define clearly in the prompt when and how to use data from custom functions. For example: “After calling the order lookup function, tell the customer their order status using the returned order_status field.”

Example Flow