Voicemail detection
Overview
Section titled “Overview”The Voicemail Detection tool allows your ElevenLabs agent to automatically identify when a call has been answered by a voicemail system rather than a human. This system tool enables agents to handle automated voicemail scenarios gracefully by either leaving a pre-configured message or ending the call immediately.
Functionality
Section titled “Functionality”- Automatic Detection: The LLM analyzes conversation patterns to identify voicemail systems based on automated greetings and prompts
- Configurable Response: Choose to either leave a custom voicemail message or end the call immediately when voicemail is detected
- Call Termination: After detection and optional message delivery, the call is automatically terminated
- Status Tracking: Voicemail detection events are logged and can be viewed in conversation history and batch call results
Parameters:
reason(string, required): The reason for detecting voicemail (e.g., "automated greeting detected", "no human response")
Function call format:
{
"type": "function",
"function": {
"name": "voicemail_detection",
"arguments": "{\"reason\": \"Automated greeting detected with request to leave message\"}"
}
}Configuration Options
Section titled “Configuration Options”The voicemail detection tool can be configured with the following options:
- Voicemail Message: You can configure an optional custom message to be played when voicemail is detected. This message supports dynamic variables, allowing you to personalize voicemail messages with runtime values such as
{{user_name}}or{{appointment_time}}
API Implementation
Section titled “API Implementation”When creating an agent via API, you can add the Voicemail Detection tool to your agent configuration. It should be defined as a system tool:
from elevenlabs import AgentConfig, ConversationalConfig, ElevenLabs
elevenlabs = ElevenLabs(api_key="YOUR_API_KEY")
response = elevenlabs.conversational_ai.agents.create(
conversation_config=ConversationalConfig(
agent=AgentConfig(
prompt={
"built_in_tools": {
"voicemail_detection": {
"type": "system",
"name": "voicemail_detection",
# Optional: customize when the tool should be triggered
"description": "",
"params": {
"system_tool_type": "voicemail_detection",
# Optional: message left when voicemail is detected
"voicemail_message": "Sorry I missed you. I'll call back later.",
},
}
}
},
),
),
)import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";
const elevenlabs = new ElevenLabsClient({
apiKey: "YOUR_API_KEY",
});
await elevenlabs.conversationalAi.agents.create({
conversationConfig: {
agent: {
prompt: {
builtInTools: {
voicemailDetection: {
type: "system",
name: "voicemail_detection",
description: "", // Optional: Customize when the tool should be triggered
params: {
systemToolType: "voicemail_detection",
// Optional: message left when voicemail is detected
voicemailMessage: "Sorry I missed you. I'll call back later.",
},
},
},
},
},
},
});