How to Build Simple AI Agents With n8n & ChatGPT (OpenAI)

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Here we are in March 2025, and AI, to me, is a gimmick. Why? It’s smart, but it can’t do any actions. You yourself are the agent, doing the actions that you determine are best with the information that ChatGPT provides to you. So who’s the robot now, eh?

How can you remove yourself from the bottleneck? Well, it’s pretty simple. Learn how to build an AI agent with n8n and ChatGPT for your business, or hire someone to build the AI agent(s) for you! That’s what I do, and it’s what I want to teach you!

How to Build an AI Agent with n8n + ChatGPT

1. Go purchase a DigitalOcean droplet and install n8n.
2. Go purchase some OpenAI API credits.
3. Setup your n8n to have your login credentials for your third-party tools (WordPress, Gmail, SQL, Google Sheets, Salesforce, etc…).
4. Set up a trigger with open-ended options (for example, email comes into your sales@domain.com Gmail account).
5. Define the list of actions that you want ChatGPT to determine to do.
6. In n8n, go build out the action steps for each action type.
7. Push it live!

I do a much better job of explaining/demonstrating all of this it in my YouTube Video on how to create AI agents with n8n. It’s a bit hard to explain without just showing you how it can be done, so that’s a better one there.

Some Tricks to Building Your AI Agent

Define Your List of Appropriate Actions

You need to let ChatGPT know the boundaries of the actions it can list out, and what it cannot do. Provide it with all of the information necessary to do those actions.

For example, if you need it to create a work order, it needs to know for whom and how to do it (email / SMS / form entry / API call). It also needs to know where that action is. Sometimes, you can code these pieces inside of the subsequent steps in your n8n AI agent…