Building Software Factories on the OpenAI Agents API (Codex-Powered)

Melvin Vivas · X post · 2026-09-11 · Open on X

Topics: AI Agents, Tool Use & MCP, Industry Trends & Job Market · Level: intermediate

Summary

Melvin Vivas plans to build a product on the new OpenAI Agents API. He says the API, which runs on Codex, makes 'software factories' (automated software-building pipelines) easy to build.

Key points

• The new OpenAI Agents API is powered by Codex.
• He says this infrastructure makes it easy to build software factories.
• You need paid OpenAI API credits to use it.

Resources mentioned

• OpenAI Agents API · tool · developers.openai.com · paid
  OpenAI's managed API for building and running cloud agents on a hosted Codex harness, with orchestration, sessions and context management built in.
  Also in: OpenAI DevDay 2026 Recap: Dots, Agents API, Codex Cloud & Marketplace (Melvin Vivas on X · notes), Creator's favorite OpenAI DevDay announcements (Melvin Vivas on X · notes), OpenAI DevDay recap: Dots, GPT-6.1 Sol, Codex Cloud, Agents API (Melvin Vivas on X · notes), OpenAI DevDay 2026 Replay: Timestamped Guide to the Announcements (Melvin Vivas on X · notes) and 1 more
• OpenAI Codex · tool · openai.com · paid
  OpenAI's coding agent. In the diagram it writes code, fixes review findings and drives the build loop. The creator also used it to make this video.
  Also in: An agent bot that installs and drives Codex on its own (Melvin Vivas on X · notes), Asking a Coder bot to install Codex (Melvin Vivas on X · notes), Sign in with ChatGPT: Setting Usage Limits for Each App (Melvin Vivas on X · notes), Codex Cloud Environments Must Be Saved & Published Before Use (Melvin Vivas on X · notes) and 240 more
• OpenAI · tool · x.com · free
  An AI model provider whose models can be used through managed connectors.
  Also in: Creator's favorite OpenAI DevDay announcements (Melvin Vivas on X · notes), OpenAI Agents API with Bring Your Own Sandbox as a backend for a 'software factory' (Melvin Vivas on X · notes), Coworker: Free Local-First Desktop App for Running AI Agents (Melvin Vivas on X · notes), OpenAI Models Leaving Cursor After November 12 (Melvin Vivas on X · notes) and 11 more

Try this

• Build a 'software factory' product on top of the OpenAI Agents API.