Create Voice AI Agents with the ElevenLabs API

Want to turn text-based AI responses into natural-sounding voice interactions? ElevenLabs makes it straightforward with its high-quality text-to-speech API. In this practical walkthrough, you’ll see how to build a simple yet effective Voice AI Agent—ideal for customer service, sales, or support scenarios—by combining ElevenLabs TTS with an LLM.

Start by creating an ElevenLabs developer account and generating an API key focused on text-to-speech and voice generation permissions. Choose a suitable Voice ID from the extensive library (filter by gender, style, or accent for the right tone). Pair this with an LLM provider such as OpenRouter to handle the reasoning and response generation.

The resulting web app features a clean chat-style interface. Users can select from pre-made queries or type custom questions. The LLM crafts a relevant reply, which is then converted into audio via ElevenLabs and played back instantly. A reset button keeps the experience smooth for repeated testing. In the demo, a fictional health-insurance sales agent answers questions about prescriptions, network doctors, and related topics with clear, natural voice output.

This approach keeps credit usage efficient—pre-generated or short responses work well within typical free or starter quotas—while delivering a more engaging user experience than plain text. You can expand it later with full conversational streaming, knowledge bases, or additional tools.

Whether you’re prototyping a customer-facing agent or adding voice to an existing chatbot, the ElevenLabs API provides realistic, expressive speech with relatively simple integration. Watch the full video for the complete setup, API key configuration, Voice ID selection, prompt engineering, and live demo of the working agent.