AI Glossary
Hallucination (AI)
Also known as: Confabulation
A hallucination is when an AI model produces false or non-existent information that looks true, such as a made-up quote, number or reference.
Why it happens
LLMs are trained to produce plausible text, not to check facts. When information is missing, they fill the gap with what “sounds right”.
How to reduce it
- Provide sources in the prompt (RAG) and ask the answer to cite them.
- Let the model say “I don’t know”.
- Ask for verifiable answers: links, numbers with a source.
- Always review when a mistake has a cost.
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