ChatGPT Codex Review (May 2026): GPT-5.5 Backbone Leads Terminal-Bench 83.4% — Better Than Claude Code?
🆕 Latest Update (May 30, 2026): ChatGPT Codex moved meaningfully forward through 2026. Current backbone: GPT-5.5 (replaced GPT-5.3-Codex), with 88.7% SWE-bench Verified — essentially tied with Claude Opus 4.8 (88.6%). More notably, Codex CLI on GPT-5.5 leads Terminal-Bench 2.1 at 83.4% — ahead of Claude Code (78.9%) and Gemini CLI (70.7%). Bundled into $20 ChatGPT … Read more