Developers Ditch Claude Opus 5 for OpenAI Codex After Quality Decline

Developers report Claude Code (Opus 5) has become noticeably dumber, making basic mistakes like omitting logging in long tasks; after switching to OpenAI Codex, they found it faster with better code and text quality.

2026-08-31 ~ 2026-08-31 · 3 related posts

• Developer Switches from Opus 5 to Codex Citing Better Performance — sirbayes · 2026-08-31
• Dev Switches Back to Codex Due to Claude Code Quality Drop — andersonbcdefg · 2026-08-31
• Developer finds Codex superior to Codeium Opus 5 — deliprao · 2026-08-31