This Voice AI Agent Can Handle EVERYTHING (No-Code Tutorial)

Key Concepts

• Voice AI Agent: An artificial intelligence system capable of understanding and responding to spoken language, used here for lead qualification and appointment booking.
• Lead Qualification: The process of identifying and evaluating potential customers (leads) to determine their likelihood of purchasing a product or service.
• No-Code AI Tools: Platforms that allow users to build AI applications without writing traditional code, such as Retell AI and Naden.io.
• Real-time GPT: A highly responsive AI model that minimizes latency in voice interactions, making them more natural.
• Dynamic Variables: Placeholders in a script that are populated with specific data (e.g., customer name, phone number) during an interaction.
• Webhooks: A mechanism that allows one application to send real-time data to another application when a specific event occurs (e.g., form submission).
• API Key: A unique identifier used to authenticate and authorize access to an API (Application Programming Interface).
• Knowledge Base: A repository of information that an AI agent can access to provide more informed responses.
• Call Transfer (Cold/Warm): The ability for an AI agent to transfer a call to a human agent, either directly (cold) or after providing context (warm).

Building a Voice AI Lead Qualification System

This video details the step-by-step process of building a voice AI agent that automatically contacts customers immediately after they submit a form on a website, qualifies them, and can even book appointments. The primary goal is to leverage the significant increase in conversion rates (391% when contacted within 60 seconds) by automating this rapid response.

1. The Power of Immediate Response and Voice AI

• Key Statistic: Contacting a customer within the first 60 seconds of a form submission increases their buying chances by 391%.
• Problem: Most businesses cannot achieve this speed manually.
• Solution: A voice AI agent that automates the immediate follow-up call.
• Benefits: Professional interaction, lead qualification, asking key questions, and appointment booking.
• Target Audience: Businesses aiming to boost sales and freelancers offering AI services.
• Incentive: The presenter offers the main prompt for the voice AI agent for free and promises a guide to becoming a certified voice AI expert.

2. Demo of the Voice AI Agent

A live demonstration showcases the system in action:

• A form on a website (specifically for "AI workshop AI agency") is filled out by a user.
• Upon submission, the user receives an immediate call.
• The voice AI agent, "Cindy," initiates a professional conversation.
• Key Interaction Points:
  • Identification: "Hello. Am I speaking with Sue Bear Trebzada?"
  • Purpose: "Great. This is Cindy from AI workshop AI agency. Am I catching you at a good time? ... You recently filled out a form about AI solutions and I'm here to ensure you're connected with the right specialist."
  • Qualification (Urgency): "Could you let me know if you're looking to get started immediately or if you're still in the research phase?" (User responds: "looking to start immediately.")
  • Addressing Inquiry: The AI explains how they got the number by referencing the form submission.
  • Qualification (Budget): "Can you confirm your budget? You mentioned roughly $5,000 to $10,000. Does that still hold true?" (User confirms.)
  • Appointment Scheduling: "Could you share a preferred day and time range? For instance, between 9:00 a.m. and 12:00 p.m. on Wednesday or Thursday?" (User suggests: "Monday between 9:00 a.m. to 11:00 a.m.")
  • Handling Interruption: The user interrupts to state they need to go. The AI gracefully acknowledges this and confirms the scheduled follow-up time.
• AI Capabilities Demonstrated: Natural conversation flow, handling interruptions, lead qualification (urgency, budget), and appointment scheduling.
• Underlying Technology: The natural interaction is attributed to using "GPT real time," a fast AI model.

3. Building the System: Tools and Setup

The system is built using two primary no-code platforms:

• Retell AI: For the voice agent front-end.
• Naden.io: For the back-end workflow automation.

Both platforms offer free accounts.

3.1. Setting up the Retell AI Agent

1. Create an Account: Sign up for a free account on Retell AI.
2. Navigate to Agents: Go to dashboard.ai.com/agents.
3. Create a New Agent:
   • Click "Create an agent."
   • Select "Voice agent."
   • Choose "Single prompt agent."
   • Click "Start from blank" and then "Create."
4. The Universal Prompt: This is the core of the agent's personality and script.
   • Free Prompt: The presenter provides a pre-written prompt via a Word document link.
   • Prompt Structure:
     • Persona: Defines the agent's identity (e.g., "You're Cindy, an AI powered voice assistant for AI workshop AI agency."). This can be customized for different businesses.
     • Script: A step-by-step guideline for the conversation, including:
       • Greeting and Identification: "Hello, am I speaking with [name]?" (using a dynamic variable).
       • Handling No Answer: Options to leave a message or not.
       • Stating Purpose: Explaining the reason for the call based on the form submission.
       • Lead Qualification: Assessing urgency and budget.
       • Appointment Booking: (Optional, discussed later).
   • Dynamic Variables: The prompt uses placeholders like [name] which will be populated with data from the form submission via Naden.

3.2. Setting up the Naden.io Workflow

Naden.io handles the automation and integration between the form submission and the Retell AI agent.

1. Create an Account: Sign up for a free account on Naden.io.

2. Create a New Workflow: Start with a blank canvas.

3. Import Blueprint (Optional but Recommended): The presenter mentions having a downloadable JSON blueprint for this specific workflow, which can be imported via the three dots menu -> "Import from file."

4. Workflow Steps:

   • Trigger: Form Submission (Naden Form or Webhook)

     • Naden Form: Use Naden's built-in form for simplicity.
       • Form Title: "Lead Qualifier"
       • Form Elements: Add fields like Name (text, required), Email (email, required), Phone (number), Budget (dropdown with options like "2 to 5k", "5 to 10k", "10 to 20k"), and Service (textarea).
     • Webhook: Alternatively, use a webhook to connect to a form on your own website. This involves getting a webhook URL from Naden and configuring it in your website's form submission.

   • Action: HTTP Request (to Retell AI)

     • Purpose: This node makes an API call to Retell AI to initiate the phone call.
     • Configuration:
       • Method: POST
       • URL: The Retell AI endpoint for creating a phone call (found in Retell AI's API documentation).
       • Authentication: Custom OAuth with an API key obtained from Retell AI's "Limits" section.
       • Body:
         • from number: The phone number purchased from Retell AI (e.g., $2 per number). This can be bought directly or connected via Twilio.
         • to number: The customer's phone number, dynamically pulled from the form submission.
         • agent_id: The unique ID of your Retell AI agent.
         • voice_id: (Optional) Specifies the voice for the AI.
         • language: (Optional) Specifies the language.
         • custom_message: (Optional) A message to be spoken by the AI.
     • Dynamic Data Mapping: Drag and drop data from the form submission (e.g., customer name, phone number, budget) into the HTTP request body.

   • Action: Google Sheets (Append/Update)

     • Purpose: To log all submitted lead information into a Google Sheet for CRM purposes.
     • Configuration:
       • Credentials: Sign in with Google to authorize Naden.
       • Sheet Resource: Select your Google Sheet (e.g., "Lead Qualification").
       • Sheet: Select the specific sheet tab (e.g., "Sheet1").
       • Column Mapping: Map the fields from the form submission (Name, Email, Phone, Budget, Service) to the corresponding columns in your Google Sheet.
       • AI Phone Summary: An optional column to store a summary of the call transcript.

   • Action: Webhook (from Retell AI to Naden)

     • Purpose: To receive the call transcript and summary from Retell AI after the call is completed.
     • Configuration:
       • Retell AI Webhook Settings: Copy the webhook URL provided by Naden and paste it into Retell AI's webhook settings.
       • Naden Webhook Node: This node receives the data from Retell AI.
     • Summarization Chain (Optional):
       • A chain of nodes that processes the call transcript to generate a summary.
       • This summary can then be appended to the Google Sheet.
     • Update Google Sheet (with Summary): Another Google Sheets node to update the "AI Phone Summary" column with the generated summary.

4. Retell AI Agent Configuration Details

• AI Models:
  • GPT Realtime Mini: Recommended for natural, low-latency interactions (approx. 12 cents/minute).
  • GPT5 Mini/GPT5: Cheaper alternatives but with higher latency.
  • Latency Measurement: The presenter shows how changing models affects latency (e.g., GPT Realtime Mini has ~495ms latency, while GPT4.1 has ~1675ms).
• Voice Selection:
  • OpenAI voices are available if using OpenAI models.
  • If using other models (like Claude), voices from 11 Labs, Cartisia, or OpenAI can be selected. Cartisia is noted for good voice models.
• Language: Supports multilingual or specific languages like English.
• Functions:
  • End Call: Automatically included.
  • Transfer Call:
    • Cold Transfer: Immediately transfers the call to a specified number.
    • Warm Transfer: Allows for providing context before transferring.
    • Implementation: Add a "Call Transfer" function and input the transfer phone number.
  • Book Appointment (Advanced):
    • Can be integrated using tools like Calendly or Cal.com.
    • Requires additional setup and tutorials are available.
• Knowledge Base:
  • Purpose: Provides the AI with additional context and information.
  • Implementation: Upload documents (e.g., FAQs) or website links. The prompt can then instruct the AI to refer to this knowledge base.
  • Example: The presenter refers to an "AI workshop FAQ" document.
• Welcome Message: Configure the initial message the AI speaks when the call connects.

5. Becoming a Voice AI Expert

• Community: The presenter promotes their community for learning and support.
• Courses: Step-by-step courses are available for Naden.io (beginner to expert) and Voice AI agents.
• Certification: A "Voice AI Agent Certification Program" is offered in partnership with Retell AI.
• Tech Support: Dedicated tech support is available for different sections of the platform.

Conclusion

This comprehensive guide demonstrates how to build a powerful, automated voice AI lead qualification system using Retell AI and Naden.io. By leveraging immediate contact and AI-driven conversations, businesses can significantly improve their lead conversion rates. The presenter provides a free prompt and detailed instructions, making the system accessible even for those new to AI development. The potential for offering this as a service or integrating it into existing business workflows is highlighted, along with opportunities for further learning and certification.