I brought ChatGPT, Claude, and Gemini into a group chat to solve a complex problem. Here is how they caught each other hallucinating

You probably know how it goes: you give a complex prompt to a LLM, it spits out a highly confident answer, and you just sort of... hope it’s right. If you ask the same question in a different tab, Claude might give you a completely different answer. Gemini might say they are both wrong. I've done it this way for a long time, and many of my friends seem to do the same.

I wanted to see what happens if you don't just compare answers, but actually bring AI models into a shared chat to discuss the question together. Here is how it went when they could discuss each other's replies in real-time:

- ChatGPT went first. It wrote a beautiful, highly structured, and completely wrong answer. It hallucinated a tax rule that didn't apply to the prompt.

- Claude stepped in next. It immediately flagged GPT’s tax hallucination, but overcorrected and messed up the final math equation.

- Gemini acted as the final Judge. It took ChatGPT’s original structure, applied Claude’s logical correction, fixed the math, and spat out a flawless final output.

The takeaway:
Letting an AI model review itself is like a student grading their own work. It just repeats the same assumptions. When you force different models (OpenAI vs Anthropic vs Google) to fact-check each other, they actually expose each other's blind spots and hallucinations.

I got so obsessed with this multi-AI workflow that I built a site to let these models debate in real-time without having to copy-paste between different tabs (I posted about it earlier here). If anyone wants to try it or testing their own complex questions, curious to hear what kind of workflows you guys would use it for.