The 5 Biggest Mistakes When Starting with AI Agents

My first AI agents were... not good. To be honest: they were a disaster.

I made mistakes that cost me weeks of time. Mistakes you don't have to repeat.

In this article, I'll show you the 5 biggest mistakes – and how to avoid them.

I'm not telling you this because I enjoy showing my mistakes. But because I know you'll make the same mistakes if no one tells you about them.

So: Learn from my mistakes. It's cheaper.

1. Too Many Permissions Too Early

At the beginning, I gave my agents full access to everything. Admin rights. API credentials. All of it.

I thought: "The more permissions, the better."

That was a mistake.

The result: My email agent sent a "creative" response to a customer that... well, it wasn't meant for external eyes. It was an email I had drafted to edit later. The agent sent it.

The customer was... confused. To put it diplomatically.

I spent an hour apologizing. And another hour reworking the permissions.

The lesson: Start small. Your agent earns permissions. First read, then write. First test environment, then production.

Today, every agent I start has minimal permissions. Like an intern who first only watches. Once they've proven they can do it, they get more.

2. No Clear Rules Defined

Without clear instructions, the agent does what it wants. It's like a new employee without onboarding.

I thought "be helpful" was a sufficient instruction. It wasn't.

My agent started replying to emails I would have rather answered myself. It moved appointments I didn't want moved. It used "creative" phrasing that didn't match my style.

The lesson: SOUL.md and AGENTS.md are not optional. The more precisely you define who the agent is and what it's allowed to do, the better the results.

In my course, I show you exact templates for:

• Personality profiles
• Decision frameworks
• Boundaries and guardrails
• Communication rules

It took me months to get this right. In the course, I show you how to get it done in a few hours.

3. Connected Email Without Testing

Once I wanted to be fast. I connected email live without testing properly first.

I thought: "It'll probably be fine."

The result: 47 automated responses to the wrong people. Embarrassing.

What happened: My agent was supposed to reply to incoming emails. But it replied to every email – including spam, newsletters, and automatic out-of-office replies.

A customer wrote to me afterward: "Jan, is everything okay? You replied to the same newsletter three times."

I was mortified.

The lesson: Always test with dummy accounts first. Only go live when everything works.

Today, I use a separate test Gmail account. All my tests run there. Only when everything is correct does it go to the real accounts.

4. No Monitoring

At first, I had no idea what my agents did during the day. I just assumed they were doing their work.

That was a mistake.

Once I checked after a week and found: My agent had answered 200 emails – but 30 of them were completely wrong. It didn't understand the questions and just answered something.

Customers looked at me strangely afterward.

The lesson: Implement logging from the start. I use a simple dashboard that shows me:

• How many tasks completed
• Which errors occurred
• What needs optimization
• Which actions are most common

That changed my life. Now I can see at a glance what's going on – and intervene when something goes wrong.

5. Expected Everything to Work Immediately

My first setup took 3 weeks to run properly. And I thought I was doing something wrong.

I was frustrated. I wanted to give up. I thought: "This is all nothing."

That's not true. It's an iterative process.

At the beginning, Emma, my assistant, was terrible. She completely misunderstood emails. She entered appointments in the wrong timezone. She sent me notifications that were completely useless.

And now? Now she's my most important team member.

The lesson: Give yourself time. The agents get better the more you use them. It's like with a new employee – at first everything is slow, over time it gets better.

I trained Emma over 6 months. Every day a little better. Every day a few more rules. And today she's indispensable.

What I Do Differently Now

Today, I start every new agent like this:

1. Step 1: Read-only access (e.g., read emails, but don't reply)
2. Step 2: Supervised replies (I have to approve every draft)
3. Step 3: Fully autonomous (when trust is built)

This is slower – but safer.

I've also learned: Document everything. What works, what doesn't, which rules are important. That helps you avoid problems later.

My Most Important Tip

The biggest mistake would be not starting at all.

I know this sounds like a lot. I know you might be thinking: "This isn't for me."

But a year ago, I thought the same way. And today?

Today I wonder how I ever worked without agents.

In the course, I show you my ready-made setups so you don't have to repeat these mistakes. I show you exactly what I did wrong – and how you do it better.

→ Get the AI Agent Crash Course – €49 (Early Bird)

The 49€ is cheaper than the time you'll spend making mistakes. Trust me – I speak from experience.