OpenAI Shows How to Build with Codex Harness via Agents API

At a glance

This video from OpenAI's DevDay 2026 introduces how to use the Codex harness (the base framework that runs and manages AI agents) through the Agents API (an interface for AI that carries out tasks on its own). According to the description, it covers running agents in your own environment, keeping long-running tasks going, and which infrastructure OpenAI manages.

What the video covers

1. 1

   How to run agents in your own environment

2. 2

   How to keep long-running tasks going

3. 3

   The scope of infrastructure OpenAI manages

Why watch it?

It helps developers and business leaders who want to build or adopt AI agents understand how they are run.