Hallucination
Expanded definition
In product terms, hallucination is an ungrounded claim: a fake citation, invented API, or confident wrong number. RAG, tool use, and structured extraction reduce it by constraining what the model may say. Evaluation should score faithfulness separately from style. Do not treat a refusal as a hallucination, and do not treat a hedging phrase as proof of truth.
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Hallucination FAQ
What is Hallucination?
Hallucination is fluent model output that is not supported by the provided context or by checkable facts.
How is Hallucination used in AI systems?
In product terms, hallucination is an ungrounded claim: a fake citation, invented API, or confident wrong number. RAG, tool use, and structured extraction reduce it by constraining what the model may say. Evaluation should score faithfulness separately from style. Do not treat a refusal as a hallucination, and do not treat a hedging phrase as proof of truth.
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