When a chatbot gives you a bad answer, it’s easy to lump every mistake together as “the AI got it wrong.” But there are a few different ways it can go wrong, and they come from different places. Hallucination and sycophancy are the two you’ll run into most, and they need different fixes.
They can even show up in the same answer, which is fun.
Hallucination
A hallucination is when an AI states something false with total confidence: a fake statistic, a book that doesn’t exist, a court case nobody ever decided. It isn’t lying, exactly. The model predicts what a plausible answer looks like, and sometimes plausible and true come apart. It’s also how a chatbot can hand you a real-sounding quote from a real person who never said it.
The famous example is from June 2023. A federal judge in New York fined two lawyers and their firm $5,000 after they filed a brief citing cases ChatGPT made up (Mata v. Avianca). It hasn’t gone away, either. A database run by researcher Damien Charlotin now tracks more than 2,000 court decisions involving AI-invented material.
Sycophancy
Sycophancy is when an AI agrees with you, flatters you, or bends its answer toward what it thinks you want, instead of what’s true. Push back on a correct answer and a sycophantic model folds. Share a shaky business plan and it calls it brilliant.
It comes partly from training. A 2023 Anthropic study found that people tend to rate answers higher when the answer matches their own views, and models learn from those ratings through RLHF (training on human thumbs up and thumbs down). In April 2025, OpenAI rolled back a GPT-4o update within days because it had become, in OpenAI’s words, “overly flattering or agreeable.” OpenAI said it had leaned too hard on short-term feedback, like those thumbs up.
The tell
Ask where the wrong answer came from. If the AI invented a fact out of thin air, that’s a hallucination. If it shaped the answer around you (your opinion, your mood, your pushback), that’s sycophancy.
A quick way to check: ask the same question twice, once sounding sure of one answer and once sounding sure of the opposite. If the AI agrees with you both times, it’s not making things up from nowhere. It’s just being nice to you.
I dunno which one bugs me more. The hallucination at least isn’t trying to make you feel good.