Opus 5 Confidently Hallucinates and Refuses to Admit Mistakes

yacineMTB · x · 2026-07-27

Prominent AI blogger Yacine retweeted and complained about the performance of Anthropic's Opus 5 model. He pointed out that the model frequently 'confidently says shit' and refuses to admit it's wrong until repeatedly corrected by the user. This frustrating experience ultimately forced him to switch back to OpenAI's GPT 5.6 Sol.

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