elevenlabs-voice-agent

# ElevenLabs Voice Agent Build AI phone agents using ElevenLabs Conversational AI API + Twilio. ## Setup Flow 1. Create agent via ElevenLabs dashboard or API 2. Configure voice, TTS model, LLM, and system prompt 3. Purchase/connect Twilio phone number via ElevenLabs phone integration 4. Test and iterate on script, voice settings, turn-taking ## Optimal Voice Settings (Proven) | Setting | Value | Why | |---------|-------|-----| | TTS Model | v3 conversational | Best quality for phone calls | | Expressive mode | ON | Natural inflection | | Stability | 0.45 | Natural variation without inconsistency | | Similarity | 0.75 | Recognizable voice | | Speed | 1.2x | Fast enough for cold calls (API max) | | Streaming latency | 4 | Balance speed vs quality | | Turn timeout | 2s | Don't wait too long for response | | Eagerness | eager | Jump in naturally | | Speculative turn | ON | Faster responses | | Cascade timeout | 3s | Handle pauses | ## Recommended Voices - **Alexandra** (`kdmDKE6EkgrWrrykO9Qt`): Pleasant female, great for cold calls - **Hope** (`OYTbf65OHHFELVut7v2H`): Warm female backup ## LLM Choice Use `gpt-4o-mini` for phone agents — speed is critical, latency kills calls. ## Key API Endpoints ``` POST https://api.elevenlabs.io/v1/convai/agents/create PATCH https://api.elevenlabs.io/v1/convai/agents/{agent_id} GET https://api.elevenlabs.io/v1/convai/agents/{agent_id} POST https://api.elevenlabs.io/v1/convai/twilio/phone-numbers — Connect Twilio number ``` ## Enable Phone Features Enable these tools on the agent: `voicemail_detection`, `end_call`, `background_voice_detection` ## NEPQ Sales Framework For appointment-setting agents, use Neuro-Emotional Persuasion Questioning: - Permission-based opening ("Do you have a quick moment?") - Question-led qualification (don't pitch, ask) - Emotional connection questions before booking - Soft close with specific time options ## Twilio Integration 1. Get Twilio Account SID + Auth Token 2. Use ElevenLabs API to create phone number connection 3. Phone number is provisioned automatically by ElevenLabs 4. Calls route: Twilio → ElevenLabs → AI agent ## Common Issues - **Robotic voice**: Switch to v3 conversational model, enable expressive mode - **Slow responses**: Use gpt-4o-mini, increase streaming latency optimization - **Cuts off caller**: Increase turn timeout, reduce eagerness - **Sounds scripted**: Add personality to system prompt, lower stability slightly