OpenAI Launches Agents API Beta with Managed Sandboxes
On September 10, OpenAI officially released the Agents API in public beta, opening the harness that previously powered Codex to all application developers: with a single API call providing a task, model, tools, and compute environment, developers can create agents running in OpenAI's cloud, fully managed by OpenAI.
Confirmed
- Agents API is in public beta, built on the Codex harness, with OpenAI handling orchestration, long-running sessions, and context management, so developers don't need to build their own agent infrastructure (m1/m2/m3)
- An official video demoed building an agent to investigate production incidents: connecting various tools via MCP, following runbook steps for troubleshooting, and ultimately producing a follow-up report with evidence and recommendations (m1)
- Official documentation is now live, covering capabilities such as session management (creating/resuming sessions) (m5)
Why it matters
- @shaunralston argues the hard part of agent development was never the model itself, but letting AI work continuously for hours: calling tools, remembering what has been done, recovering from errors, and not drowning in massive logs—the Agents API provides exactly this scaffolding
- Developers are freed from building their own harnesses and operational infrastructure, needing only to focus on task definition and tool integration, lowering the barrier to building production-grade agents
2026-09-11 ~ 2026-09-11 · 13 related posts
Primary sources
- [source] OpenAI launches Agents API public beta: fully managed cloud agents with Codex harness — OpenAIDevs · 2026-09-11
- OpenAI details Agents API: hosted agent loop, developer-controlled code execution — OpenAIDevs · 2026-09-11
- OpenAI Agents API supports BYO sandboxes with Cloudflare, Modal, E2B, Vercel and more — OpenAIDevs · 2026-09-11
- OpenAI adds hosted sandboxes: agents can run code, work with files, produce artifacts — OpenAIDevs · 2026-09-11
- [source] OpenAI Launches Agents API: Hosted Codex Harness for Building Agents — OpenAI · 2026-09-11
- OpenAI Agents API Meets Cloudflare: Deploy a Logged Agent in 4 Minutes — craigsdennis · 2026-09-11
- [source] OpenAI launches Agents API: sessions, orchestration and evals for hour-long agents — shaunralston · 2026-09-11
- OpenAI Agents API hits public beta; Cloudflare ships sandbox integration for cloud Codex agents — ritakozlov · 2026-09-11
5 near-duplicate retellings: OpenAIDevs · nikunjhanda · Codeblix_Ltd · varunshenoy_ · irvinebroque