How to Build a LINE ChatGPT Chatbot with Zero Coding Effort

In this blog, I’ll share my experience of creating a LINE chatbot powered by OpenAI’s ChatGPT. The goal is to attach a LINE official account with an auto-reply chatbot function that responds based on the user’s current message and conversation history. The best part? No coding is required!

Example: Chatbot Conversation

Here is an example of a conversation between a user and a chatbot, showcasing the chatbot's context-aware responses:

To achieve this, you will need the following tools:

OpenAI API
LINE Official Account
MAKE Account: To automate the workflow between LINE and OpenAI.

Preparation

If you haven't set up the required tools yet, follow this instructions. Skip this section if you already have them.

1. Create an OpenAI Account and Get Your API Key

If you don’t have an OpenAI account:

Sign up at OpenAI Create Account.
Generate your first API key during account creation or later.
Important: Save your API key locally. You won’t be able to see it again!
Check OpenAI’s pricing and decide how many credits to purchase.

If you already have an account:

Log in at OpenAI Log In.
Go to Settings ⚙️ → PROJECT → API keys → + Create new secret key.

2. Create a LINE Official Account

Follow the setup guide here: LINE Official Account Setup Guide

3. Get Your Channel Access Token and Connect to MAKE

Create a MAKE account.
Connect it to LINE Developers. Refer to this guide for detailed steps (in Japanese): MAKE and LINE Integration Guide.

🚀 Build the Chatbot Workflow in MAKE

Now we get into something serious! Here’s the overall workflow:

The chatbot receives a user’s message, retrieves conversation history from the data store, aggregates the data, sends it to OpenAI, and replies to the user.

We’ll create this workflow using a MAKE scenario — a series of modules that define how data flows and transforms between services. Learn more about scenarios here.

🧩 Scenario Overview

This is the complete scenario we’ll walk through step by step:

🔍 Behind the Scenes: MAKE Modules

1. LINE → Watch Events

Add your webhook to listen for user messages. We already completed it during preparation, in step 3.

2. Data Store Retrieve & Text Aggregation

First Data Store: Retrieves the user’s message history within the last {n} minutes (you can adjust the {-2} value).
First Tools: Aggregates the historical user queries.
Second Data Store: Retrieves the chatbot’s (assistant’s) reply history within the last {n} minutes (you can adjust the {-2} value).
Second Tools: Aggregates the historical chatbot’s (assistant’s) replies.

3. OpenAI Module + Error Handling

Choose your model (e.g., gpt-3.5, gpt-4).
Setup message flow:
- Message 1: Custom system prompt
- Message 2: User query history (from Data Store)
- Message 3: Chatbot reply history
- Message 4: Latest user query
Configure temperature, top_p, and other parameters.
Add an Ignore module to handle errors. Learn more here.