Voicemail detection

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

• 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:

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{
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  "type": "function",
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  "function": {
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    "name": "voicemail_detection",
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    "arguments": "{\"reason\": \"Automated greeting detected with request to leave message\"}"
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  }
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}

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

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:

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from elevenlabs import (
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    ConversationalConfig,
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    ElevenLabs,
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    AgentConfig,
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    PromptAgent,
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    PromptAgentInputToolsItem_System
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)
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# Initialize the client
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elevenlabs = ElevenLabs(api_key="YOUR_API_KEY")
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# Create the voicemail detection tool
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voicemail_detection_tool = PromptAgentInputToolsItem_System(
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    name="voicemail_detection",
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    description=""  # Optional: Customize when the tool should be triggered
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)
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# Create the agent configuration
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conversation_config = ConversationalConfig(
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    agent=AgentConfig(
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        prompt=PromptAgent(
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            tools=[voicemail_detection_tool]
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        )
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    )
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)
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# Create the agent
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response = elevenlabs.conversational_ai.agents.create(
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    conversation_config=conversation_config
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)