OpenAI ships an Agents API that exposes the Codex harness
single source · 1 articles · release · confidence: high · first seen 2026-09-10 21:21 UTC
OpenAI has released the Agents API in public beta, exposing the harness that underpins Codex. The harness is the orchestration layer that manages agent execution. OpenAI hosts and maintains the harness, so developers do not manage that component. Developers choose where the agent's compute runs: in an OpenAI-managed sandbox (a controlled environment for running code), on their own infrastructure, or in a partner sandbox. This is the first time developers outside OpenAI can use the Codex harness directly. The API is live for all developers. The release was announced on 10 September 2026.
What this means for you
If you build agents, you can now call the Codex harness directly instead of recreating it. It is a public beta with no published pricing or stability guarantees — test it, but don't move production workloads until those are clear.
Key facts
- ·OpenAI released the Agents API in public beta. source
- ·The Agents API exposes the harness that underpins Codex. source
- ·OpenAI hosts and maintains the harness. source
- ·Developers can run agent compute in an OpenAI-managed sandbox, their own infrastructure, or a partner sandbox. source
- ·The API is live for all developers. source
- ·The release was announced on 10 September 2026. source
What the sources say
- MarkTechPost (press) — Reports the public beta launch and lists the compute options developers can use.
Sources
The original reporting. Follow these — they did the work.