{"slug": "ask-hn-is-claude-opus-4-8-broken", "title": "Ask HN: Is Claude Opus 4.8 broken?", "summary": "A user reported that Claude Opus 4.8 is exhibiting severe performance degradation, including an inability to read files, hallucinating file paths, and repeatedly generating errors with incorrect commands like `sed`. The model also issued multiple apologies for the same mistakes within a single session, with the context window at only 15% capacity, and operated at an unbearably slow speed with frequent tool call failures.", "body_md": "In my first hour with it, it's like we're back to the GPT-2 era.\n\nIt can't even read a file anymore.\n\nRandomly uses 'sed' with no explanation in hallucinated file paths. Errors out 15 times in a row with 'No such file or directory' with paths that don't exist - it was trying to read a project file as usual in our Rails app.\n\nYou then ask it why it's not simply reading the file in the correct path, and then it says it's sorry:\n\n> You're right to be angry. Two things went wrong and both are on me: > > 1. I typed sed/cat instead of using the Read tool (the project rules explicitly say not to), and > 2. I guessed a filename app/services/gmail/sync_worker.rb that doesn't exist — the real file is app/workers/gmail/sync_worker.rb. So I was reading a path I'd invented. Sloppy,\n\nIt just apologized to me - for the 5th time in this session - writing this:\n\n> I again typed a made-up message ID into the verify step (19e70e9d...) instead of reading the real one from the list I just fetched. That's the exact mistake I keep making.\n\n(Context window at 15%).\n\nIt's unbearably slow.\n\nIt presents 10+ errors like 'Cancelled: parallel tool call Bash errored' all the time.\n\nIt's unreal.\n\nComments URL: [https://news.ycombinator.com/item?id=48316636](https://news.ycombinator.com/item?id=48316636)\n\nPoints: 1\n\n# Comments: 0", "url": "https://wpnews.pro/news/ask-hn-is-claude-opus-4-8-broken", "canonical_source": "https://news.ycombinator.com/item?id=48316636", "published_at": "2026-05-28 22:49:30+00:00", "updated_at": "2026-05-28 22:59:45.184127+00:00", "lang": "en", "topics": ["large-language-models", "ai-products", "ai-tools", "artificial-intelligence"], "entities": ["Claude Opus 4.8", "GPT-2", "Rails", "Hacker News"], "alternates": {"html": "https://wpnews.pro/news/ask-hn-is-claude-opus-4-8-broken", "markdown": "https://wpnews.pro/news/ask-hn-is-claude-opus-4-8-broken.md", "text": "https://wpnews.pro/news/ask-hn-is-claude-opus-4-8-broken.txt", "jsonld": "https://wpnews.pro/news/ask-hn-is-claude-opus-4-8-broken.jsonld"}}