Can Claude Sonnet 4.5 vs GPT-5 Codex Determine the Best AI Model for Developers?

Oct 2, 2025 · 3 min read · Introduction The two AI coding models released in September 2025 have stirred considerable interest among developers. On one side, Claude Sonnet 4.5 is applauded for its superior reasoning, extensive context window, and marathon-style operation. On t...