Not only that, Opus likes to invent arcane jargons. And the longer the task runs, the harder it is to understand its output. The conversation will be filled with uncommon word choices and awkward sentence structure.

"Watermarking"

The 4.5 models were the last Anthropic models that were actually pleasant to read. Especially Sonnet 4.5 was really fun to use for non-coding purposes. I liked having it generate silly short stories while waiting for deployments to finish. Haiku 4.5 still has a small bit of that charm, but 4.6 and later models are all unbearable unless you want a simple 'this is the answer' to a question.