OpenAI

AI lab behind GPT-series models and the codex coding agent harness. Founded in a San Francisco office that is now a frequent venue for Sequoia AI Ascent (per andrej-karpathy's intro: "He actually helped co-found OpenAI right inside of this office").

Known staff referenced in wiki

• andrej-karpathy — co-founder (former)
• peter-steinberger — joined 2026 (per peter-steinberger-state-of-the-claw-2026)
• ryan-lopopolo — MTS, works on internal agent tooling; gave harness-engineering talk

Products / harnesses

• codex — coding agent harness Lopopolo's team uses exclusively ("ban my team from even touching their editors")
• GPT-series models (GPT 5.2 cited by Lopopolo as the "magic moment" — "able to do the full job of a software engineer")

Related

• claude-code — anthropic's competing harness
• cursor — IDE-based agent harness
• harness-engineering — the discipline Lopopolo articulates around these tools