Voicemail detection in Conversational AI, introduced by ElevenLabs, enhances voice agent efficiency by automatically identifying and handling voicemail systems, thus avoiding wasted interactions and costs. By using large language models (LLMs) to analyze conversation patterns for voicemail cues, businesses can strategically decide whether to leave custom messages or terminate calls, optimizing resource use. This system is particularly beneficial for large-scale operations such as outbound sales, support, appointment reminders, and lead qualification, where minimizing unnecessary interactions with voicemail systems can significantly reduce costs. The implementation is straightforward, offering quick deployment with minimal latency, and is now available across ElevenLabs' API and platform, supporting the development of more economically and functionally robust voice agents.