How to make an AI email auto responder for customer service


If you’re swamped with customer emails, you’re not alone. Responding to customer queries is a time-consuming task, often requiring a team well-versed in the technical aspects of your products.

According to a survey, 44% of customers expect an email reply within 4 hours. So, how can you make this process more efficient without compromising on customer satisfaction?

The answer lies in automation and Artificial Intelligence (AI). In this guide, we’ll explore how you can set up an automated AI email responder using Zapier, Lexy, and Gmail.

Screenshot showing how to set up an automated AI email response using Zapier.

Can I Use AI to Respond to Email?

Absolutely, you can automate your email responses in two ways:

  1. Manual Input Method: Use an AI-powered email response generator where you manually input the email content and specify its intent. Then, copy and paste the generated reply into your email.
  2. Fully Automated Method: Combine automation software like Zapier with an AI query responder API like Lexy to take care of the process from start to finish.

How Does an AI Email Responder Work?

AI email responders utilize Natural Language Processing (NLP) engines such as GPT or Claude to interpret incoming emails. These AI engines then query a database—comprising your company’s knowledge base—to find relevant answers. Once the appropriate response is determined, an AI writing model crafts a personalized reply.

Lexy offers an all-in-one service through its API to accomplish these tasks, making it an ideal choice for this setup.

Step-by-Step Guide to Setting Up Your Automated Email Responder

Step 1: Create a Lexy Account

  1. Navigate to Lexy’s Website: Go to Lexy and click on the “Sign Up” button.
  2. Notion Account Requirement: Lexy relies on Notion to store your knowledge base. Therefore, you’ll need an existing Notion account to proceed.
  3. Follow the Sign-Up Process: Complete the sign up by linking your Notion account.
Screenshot of the Lexy account creation page displaying options for integrating with Notion.

Step 2: Add Your Knowledge Base to Notion

  1. Organize Your Knowledge: Create a Notion page and populate it with FAQs or any essential information about your product. For this guide, we’ll use an imaginary product, the Softy5000 automatic ice cream maker.
  2. Use Headers and Bullet Points: Make your knowledge base easy to navigate by using headers for topics and bullet points for details.
Image of a Notion page that serves as a knowledge base for the imaginary product, Softy5000, an automatic ice cream maker.

Step 3: Create a Bot in Lexy

  1. Authorize Notion Pages: In Lexy’s dashboard, connect the Notion pages that make up your knowledge base.
  2. Name Your Bot: Give your bot a specific name that correlates to its purpose.
  3. Select Notion Pages: Choose the pages you want this bot to reference for its answers.
Screenshot of the Lexy interface for bot creation, showing options to authorize Notion pages and name your bot.

Step 4: Create a Zapier Account

  1. Go to Zapier: Navigate to Zapier’s website and sign up for a new account.
  2. Follow Registration Process: Complete the form and set up your account.
Screenshot of the Zapier homepage, emphasizing the option to create a new account.

5. Create a Zap in Zapier for Automated Email Responses

Creating a Zap—Zapier’s term for an automated workflow—connects Gmail to Lexy, automating the process of receiving and responding to emails. Below is a step-by-step walkthrough to help you build your Zap.

Step 5.1: Launch a New Zap

  1. Log in to your Zapier account.
  2. Click on the ‘Make a Zap’ button usually found at the top right corner.

Step 5.2: Set Up Your Trigger

  1. In the “Search apps” field, type “Gmail” and select it from the dropdown.
  2. Choose the trigger event, in this case, “New Email.”
  3. Click “Continue.”
  4. Now you need to sign in to your Gmail account and grant permissions to Zapier if prompted.
  5. After signing in, you can filter which emails should trigger the Zap. For example, specify a folder for customer inquiries.
  6. Click “Test Trigger” to make sure it’s working correctly.
Screenshot depicting the initial steps to create a new Zap in Zapier, focusing on email triggers.

Step 5.3: Set Up Your Webhook for Lexy

  1. In the “Do This…” section, search for “Webhooks” and select it.
  2. For the event, choose “POST.”
  3. Click “Continue.”
Screenshot showing how to set up a webhook in Zapier with POST method for Lexy integration.

Step 5.4: Configure Webhook Data

  1. In the URL field, paste the URL link you get from the Lexy API documentation. ****
  2. Under Payload Type, select “json.”
  3. Configure the data fields:
    • token: Navigate to Lexy > Bots > Your Bot > Install Me > Copy the API token.
    • chatHistory: Type in an empty array “[]”.
    • query: This should be the text content from the email that triggered this Zap. It can usually be populated from dynamic fields provided by Zapier in the form of “Email Body Plain” or “Email Body HTML,” depending on how you want to capture it.
Screenshot illustrating how to configure data fields like token and chatHistory in Zapier for Lexy API.

Click “Continue” and test this step. If configured correctly, you’ll see a message stating, ‘content: I don’t have enough information to answer your question’.

Step 5.5: Add Gmail Step for Sending Email

  1. Add a new action in your Zap workflow.
  2. Search for Gmail and select “Send Email.”
  3. Configure the action with these settings:
    • To: Result of step 1 (From Email)
    • From: Your email address
    • Subject: You can concatenate with RE: [Subject from Step 1]
    • Body: Use the result from the Webhook step, often noted as “Res Content from Step 2.”
  4. Optionally, add a message like: This response was generated by Lexy AI. If you still need help, respond to this email saying ‘Live Agent’.
Screenshot of the Gmail 'Send Email' action setup within Zapier, highlighting how to insert Lexy's AI-generated response.

Step 5.6: Publish Your Zap

  1. After testing all the steps, click on the “Publish Zap” button.
  2. Your Zap is now live and will automate responses for incoming emails based on your setup.

Step 6: Test Your Zap in Gmail

Send a test email with a query about Softy5000. Make sure your email complies with the Gmail filter settings you’ve applied, so it triggers the Zap.

Image of a test email being sent to validate the customer service inquiry automation setup.

Step 7: Receive an AI Email Response

Within about 60 seconds, check your inbox for an AI-generated response. If set up correctly, it should answer your query based on your Notion knowledge base.


Automating customer service emails using Lexy, Zapier, and Gmail isn’t just doable—it’s incredibly efficient. Your customers get timely, informative responses, and you free up time for your team to focus on other critical aspects of your business.

Need help setting this up? Reach out to us through our contact form!

Free Notion CRM Template

Free Notion CRM Template

Align your sales, marketing and support with this free Notion CRM template. Track deals, store contacts and resolve tickets like HubSpot.

Notion Knowledge Base Template

Notion Knowledge Base Template

Free customizable Notion template to centralize company knowledge. Optimize accessibility, collaboration and more with this Knowledge Base template