OpenAI GPT-5.5 Powers Codex: 82.7% Terminal-Bench 2.0, Native Windows Support, 2x Pro Usage Through May

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OpenAI rolled GPT-5.5 into Codex for Plus, Pro, Business, and Enterprise users, achieving 82.7% on Terminal-Bench 2.0 and 58.6% on SWE-Bench Pro — the strongest agentic coding benchmarks to date. The Codex app now runs natively on Windows (PowerShell + native sandbox, no WSL required), and Pro subscribers get 2x usage through May 31. Combined with GPT-5.2-Codex improvements for Windows environments, OpenAI is aggressively closing the cross-platform gap with Claude Code while pushing Codex as a competitive enterprise DevTool.