OpenAI Releases GPT-5.5, the First Fully Retrained Base Model Since GPT-4.5, With 1M-Token Context and State-of-the-Art Agentic Benchmarks
OpenAI's GPT-5.5 arrives as a ground-up retrain with a 922K-token context window, 82.7% on Terminal-Bench 2.0, and two-tier pricing starting at $5/$30 per million tokens.
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