OpenAI Ships Agents API in Public Beta, Exposing Managed Codex Harness With Sandbox and MCP

OpenAI opened public beta of its Agents API on Sept 10, exposing the managed Codex harness that handles sessions, orchestration, context compaction, and recovery so developers only supply tools and pick execution environments. Built-in features include sandbox execution for code, file editing, MCP connections, artifact generation, and multi-agent delegation, with support for self-hosted sandboxes via workspace and capability directories. Model usage is billed at standard API rates plus container rates; the service is US data-residency only and does not support Zero Data Retention.