OpenAI Releases GPT-5.2 with Three Variants for Professional Knowledge Work

Summary

On December 11, 2025, OpenAI released GPT-5.2, its most capable model series to date, optimized for professional knowledge work and long-running agentic tasks. The model shipped in three variants: GPT-5.2 Instant (optimized for speed and efficiency), GPT-5.2 Thinking (a reasoning model), and GPT-5.2 Pro (the highest-capability reasoning model). All variants feature an August 2025 knowledge cutoff and a 400K context window with 128K output. On OpenAI's GDPval benchmark — which measures well-spec