AI Voice Agent with Needle, ElevenLabs & OpenAI
Turn incoming emails into helpful voice responses. Optional triggers on emails (or manual test), answers with RAG using your Needle collection, converts to speech with ElevenLabs, and optionally emails the MP3 + text reply.
Want to automate customer support with natural-sounding voice responses? This tutorial shows how to build a voice agent workflow in Needle that answers emails with grounded, human-quality speech.
Overview
The workflow receives customer questions via email, retrieves answers from your knowledge base using RAG, converts the response to natural speech with ElevenLabs, and emails back both text and voice - turning support queries into instant, personalized voice replies.
Key Actions
- Gmail Trigger - Receives incoming customer questions via email
- AI Search - Uses RAG to find answers in your Needle Collection
- Voice Synthesis - Converts text answers to MP3 with ElevenLabs
- Email Reply - Sends text + voice file back to the customer
What You'll Need
- Needle Collection - Upload your FAQs, product docs, and support guides
- ElevenLabs Account - For text-to-speech API (choose a calm, professional voice)
- Gmail - For receiving questions and sending voice replies
How It Works
When a customer emails a question:
- The workflow triggers on new Gmail emails
- AI searches your Needle Collection using the search_collection tool
- GPT-4 generates a concise, accurate answer grounded in your docs
- ElevenLabs converts the answer to natural speech:
- Voice: Professional, calm tone
- Model: eleven_multilingual_v2
- Quality: Natural intonation, human-like pacing
- Email reply is sent with:
- Text answer (for quick scanning)
- MP3 voice file (for accessibility and personal touch)
Use Cases:
- SaaS support: Onboarding questions, feature explanations, billing inquiries
- E-commerce: Order status, product questions, shipping info
- Consultants: Client FAQs, scheduling, project updates
- Professional services: Account questions, policy info, appointment confirmations
Setup Tips
- Keep answers concise - Voice responses sound better when brief and focused
- Use quality docs - Upload clear FAQs and product guides for accurate grounding
- Test first - Use Manual Trigger to refine prompts before enabling email automation
- Voice settings: Stability 0.7 + similarity_boost 0.85 = professional, reassuring tone
- Use a Dedicated Email: Connect an email address that only receives customer support requests. You can also add recipient filters to exclude specific addresses from automated voice responses.
Wrap-up
With this Needle workflow, you can automate customer support with human-quality voice responses - perfect for SaaS companies, consultants, and e-commerce teams who want to scale personalized support without hiring more agents.