Agentic AI Glossary

Hallucination

Plausible-sounding output that is unsupported, invented, or inconsistent with the available evidence.

Illustrative conversation

  1. It cited a package version that does not exist. What happened?
  2. It generated a plausible detail instead of checking the registry; a tool-based verification would have caught it.

Definition

A hallucination, also called a confabulation, is generated content that appears plausible but is false, unsupported, or inconsistent with the supplied evidence. Fluent wording and confident tone do not make a claim reliable. Grounding the model in primary sources, using tools for current facts, requesting citations, and verifying consequential outputs can reduce the risk.

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