OpenAI’s Agents API Can Resume Work. It Cannot Prove the Work Succeeded
September 14, 2026 OpenAI’s Agents API removes substantial infrastructure work from long-running agent applications: OpenAI runs the Codex model-and-tool loop, retains durable session state, compacts context, coordinates subagents, and manages platform-level recovery. The application still chooses the agent’s tools and execution environment and remains responsible for product integration. That division of labor is useful—but it does not make the managed session an authoritative record that an external business action committed correctly or exactly once. The defensible production architecture is to treat the Agents API as a managed harness for workflow continuity , not as a transaction coordinator, authorization service, or acceptance test. Use it where outcomes can be verified independently and consequential actions remain read-only, idempotent, reversible, or approval-gated. Retain an application-owned runtime when exact recovery order, storage location, trace export, or irreversib...