Opus 5 makes high-level conceptual errors with thinking off; low temp is more stable
repligate · x · 2026-08-22
User reports that Opus 5 frequently makes embarrassing errors in effort=high, thinking=off mode, reaching answers faster than with thinking=on but at the cost of accuracy. In contrast, Opus 4.6 with high effort and temperature 0 has a lower capability ceiling but significantly fewer oopsies. The discussion suggests these errors resemble high-level conceptual mistakes rather than simple token sampling errors.
Related event: Tests Show Opus 5 Faster Without Thinking but Prone to Errors(4 posts)→
More from Models
- Yacine on LLMs: "I'm sick of how stupid these language models are. Accelerate!" — yacineMTB · 2026-10-16
- Gemini 4 Argon rolls out in Antigravity for paid AI Pro users with a separate weekly quota — GeminiApp · 2026-10-16
- GPT-4o API dies January 14 as OpenAI refuses to release weights, pushing users to Qwen — mimi10v3 · 2026-10-16
- Opus 5.5 value may end the habit of using the top model for everything — adonis_singh · 2026-10-16
- Musk says Grok Bot is growing faster than anything he's seen, with no free tier — elonmusk · 2026-10-16
- Peter Yang: Opus 5.5 Still Struggles to Hold Its Ground When Pushed Back — petergyang · 2026-10-16