McGrath: Design specs let Codex complete hours of coding in 15 minutes
Josh McGrath · [State of Post-Training] From GPT-4.1 to 5.1: RLVR, Agent & Token Efficiency — Josh McGrath, OpenAI · Dec 31, 2025 · at 3:50
Josh McGrath, an OpenAI post-training researcher, describes how AI coding tools like Codex have restructured his software engineering workflow.
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“If I spend, like, you know, 30, 40 minutes writing something that looks like a design doc or something, Codex can do more work than I can do in a few hours in, like, 15 minutes.”
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