OpenAI open-sources Codex Harness for building coding agents
HarperSCarroll · x · 2026-09-30
OpenAI has launched Codex Harness as an open-source project, as highlighted by Harper Carroll. A harness is the scaffolding around a model that lets coding agents run tasks, and developers can now build their own Codex workflows on top of it.
Related event: OpenAI open-sources the Codex harness(4 posts)→
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