Accuracy and hallucinations are among the most misunderstood aspects of modern AI systems, because the problem is rarely about whether a single answer is right or wrong, but about how models behave when tasks become complex, multi-step, tool-driven, and embedded inside real professional workflows. OpenAI’s ChatGPT 5.2 and xAI’s Grok 4.1 both claim significant improvements in factual reliability, yet they rely on different evaluation philosophies, different tooling assumptions