WhatsApp AI Chatbot: How to Train One on Your Business

How to build a WhatsApp AI chatbot that answers from your own documents, products and policies, hands over to people, and keeps AI costs under control.

Short answer: a WhatsApp AI chatbot uses an AI model — such as OpenAI's GPT, Google Gemini or Anthropic's Claude — to answer customers in their own words, on your WhatsApp number. To make it useful rather than risky, give it your own information (prices, policies, products), clear instructions, a limit on how long it runs, and a way to hand the chat to a person. You build it on the WhatsApp Business API; the WhatsApp Business app can't run one.

This guide shows how to set one up in MotherBot, how to write its instructions, what it costs, and how to stop it making things up.

AI chatbot vs a button chatbot

A button chatbot follows the steps you draw: menus, questions, branches. It's predictable, and perfect for bookings, payments and order tracking. An AI chatbot writes its own answer to whatever the customer types, which handles the long tail of questions you'd never draw a button for.

The best WhatsApp bots use both: buttons for the paths you know, AI for everything in between, and a person when neither works. How to build a button chatbot.

What you need

• Your number on the WhatsApp Business API. How to get it.
• An account with an AI provider — OpenAI, Google Gemini, Anthropic or another — and its API key. The provider bills you directly for what you use.
• A MotherBot plan that includes AI. Answering from your own documents, and AI that takes actions, start on the Growth plan. See what each plan includes.
• Your information in writing: prices, timings, delivery areas, return policy, product details, common questions and their answers.

How to build a WhatsApp AI chatbot, step by step

1. Connect your AI provider

Add your AI provider's key in MotherBot. You choose the provider and the model. A smaller, faster model is usually enough for customer questions and costs less per answer.

2. Build a knowledge base

Open Knowledge Base, create one, and add your information: upload a file (.pdf, .txt, .md, .csv or .json), add a page from your website, or paste text. Keep separate knowledge bases if you have separate businesses or languages.

Write documents the way a customer asks. "Do you deliver to Pune? Yes, in 2–3 days" works better than a long policy page.

3. Start from a template, or ask MotherBot AI

Under Chatbots → Templates there are AI-ready bots to start from — AI Business Assistant, AI Customer Support (Loop + Escalation), AI + Human Handoff Bot, AI Lead Qualifier, AI Appointment Booking and AI Product Advisor & Sales Closer. Or describe what you want to MotherBot AI and it drafts the chatbot for you to check.

4. Set up the AI Reply step

In the chatbot, add an AI Reply step and set:

• Provider and model.
• Instructions — who the bot is, what it may talk about, and what to do when it doesn't know (see the example below).
• Knowledge base — so it answers from your information.
• Memory — how many earlier messages it remembers (between 1 and 30).
• A limit on AI turns — how many times it may answer in one conversation before moving on.
• What happens if the AI fails — keep trying, move to the next step, or hand to a person.

5. Let it take actions (optional)

On plans with AI Agent Tools, the AI can do things mid-conversation — look up an order or hand the chat to a person — instead of only writing text. On the top plan, an AI Product Search step can find products in your catalogue from a description like "red cotton kurta under ₹1,500".

6. Add the hand-over

Make sure every path can reach a person: an Assign to Agent step, a "Talk to us" button, and the AI's own instruction to hand over when it isn't sure. The chat lands in Live Chat with everything the customer already said.

7. Test with real questions

Switch the bot on and message your number from a personal phone. Ask the 20 questions customers really ask — and five they shouldn't. Read the Conversations log, fix the knowledge base where answers were weak, then test again.

Writing the instructions: an example

You are the WhatsApp assistant for Glow Salon in Indiranagar, Bengaluru. Answer only questions about our services, prices, timings, location and bookings, using the knowledge base. Keep answers to 2–3 short sentences. Reply in the language the customer uses — English, Hindi or Kannada. If you don't know the answer, or the customer is unhappy, asks for a refund or asks for a person, say "Let me connect you with our team" and hand over. Never make up prices or offers.

Short, specific and with a clear "when in doubt" rule beats a page of clever prompting.

What a WhatsApp AI chatbot costs

1. Your MotherBot plan. AI replies on your own AI account start on the first paid plan. See pricing.
2. Meta's reply charges. The first 1,000 replies each month on each number are free, then ₹0.115 each in India, billed to your own WhatsApp Business Account.
3. Your AI provider. Billed directly by OpenAI, Google, Anthropic or whoever you choose, at their rates. MotherBot sells no AI credits and adds nothing on top.

Two habits keep all three low: answer in one complete message rather than several short ones, and cap how many AI turns one conversation can take.

How to stop it making things up

• Answer from the knowledge base, and tell it to say "I'm not sure" rather than guess.
• Keep it on topic with narrow instructions.
• Hand money matters to people: refunds, complaints, custom quotes.
• Use buttons for anything exact — bookings, payments, order numbers.
• Read a week of AI conversations before you trust it with more.

Frequently asked questions

Can I connect ChatGPT to WhatsApp?

Yes, through the WhatsApp Business API and a platform like MotherBot. Add your OpenAI key, then use an AI Reply step in your chatbot. You can use Google Gemini, Anthropic and other providers the same way.

Can a WhatsApp AI chatbot answer from my own documents?

Yes. Add files, web pages or text to a knowledge base and point the AI Reply step at it, so it answers from your information instead of guessing. Knowledge bases start on the Growth plan.

Is a WhatsApp AI chatbot free?

The chatbot builder is on every MotherBot plan, free included, and MotherBot AI can draft bots for you on every plan. AI replies to customers use your own AI provider account, which starts on the first paid plan, and that provider bills you for what you use.

Will the AI chatbot reply in Hindi?

Yes. Modern AI models answer in Hindi, Hinglish and other Indian languages. Say in the instructions which languages to use.

What happens when the AI doesn't know the answer?

If you've told it to, it says so and hands the chat to your team, with the full conversation. You can also set what happens if the AI provider fails: try again, move on, or hand over.

Can the AI chatbot message customers first?

No. Like any chatbot on WhatsApp, it replies within 24 hours of a customer's message. To start a conversation you need an approved template.