AI agents and technology

What is an AI hallucination? Definition and examples

Also: Confabulation

In short

A hallucination is a statement by an AI that sounds convincing but is false or unsupported. Language models produce likely sentences, not checked facts. When the right context is missing, they fill the gap with invention.

Why it matters: Hallucinations show where your AI lacks context.

Why does Hallucination matter for your company?

A language model writes, word by word, what is most likely to come next. Usually that is right; sometimes it produces a source, a clause or a number that does not exist. The danger is the tone: what is wrong sounds just as sure as what is right.

In companies some errors come not from invention but from outdated material: the AI correctly quotes a document that no longer applies. You reduce both the same way, with valid context and sources. Where errors are costly, a person checks as well.

Example: The invented customer commitment

An account manager asks an AI assistant to summarise the agreements with a key customer. The assistant names a discount commitment for 2027 that was never made. It sounds plausible, because similar commitments exist with other customers.

The team changes two things. The assistant may only state commitments with a source and otherwise writes “not supported”. And a person checks every summary that goes to customers before it is sent.

3 common mistakes to avoid

  • Waiting for a better model

    Newer models hallucinate less often, but they still do. Without your context even the best ones guess.

  • Not asking for sources

    An answer without a source cannot be checked. Ask for evidence, especially for numbers, commitments and legal questions.

  • Checking everything equally

    A brainstorm needs no approval, a customer offer does. Check by consequence, not by gut feeling.

Step by step

  1. 1

    Provide valid context

    The more your AI reads from maintained sources, the less it has to guess.

  2. 2

    Require sources

    Factual statements come with a source or with the note “not supported”.

  3. 3

    Check by consequence

    A person checks anything that leaves the company or costs money.

  4. 4

    Report errors

    Record where the AI was wrong and close the gap in its context.

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