Claude Opus 4.6 vs Codex 5.3: Which AI Wins for Developers

Anthropic dropped Claude Opus 4.6 on February 5th at 9:45 AM PST. OpenAI responded 15 minutes later with GPT-5.3 Codex. Both companies had planned a coordinated 10 AM launch, but Anthropic jumped early. Within an hour, Reddit lit up with developers t...