Using Codex Subagents to Produce a Video End-to-End with No Manual Edits

Melvin Vivas · X video post · 2026-09-10 · 0:18 · 820 views · Open on X

Topics: AI Agents, Tool Use & MCP, AI Dev Tools & Productivity · Level: intermediate

Summary

Melvin Vivas shows an 18-second promo-style video that he says OpenAI Codex made with subagents and no manual editing. According to the caption, separate subagents found and downloaded b-roll and music, produced the voiceover and motion graphics, and reviewed the result. The post is a short demo of splitting a creative pipeline across multiple agents. It does not explain how the setup works.

Key points

• Codex can coordinate subagents, each handling one part of a larger multi-step task such as making a video.
• The pipeline in the caption covers sourcing b-roll, sourcing music, producing the voiceover, adding motion graphics, and a final review pass.
• The creator says the finished video needed no manual edits.
• Giving one agent the review step acts as a built-in quality check before output.
• The sample output is a short ad for an AI assistant called 'Coworker' ('remembers what matters, brings the right skills and keeps you in control').
• The post gives no prompts, configuration, or tool details. It's a capability demo, not a tutorial.

Resources mentioned

• 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
• Coworker (donvito/coworker) · repo · github.com · free
  The creator's local-first desktop app where you pick an AI coworker and have it produce work such as invoices as finished PDFs.
  Also in: Claude Opus 5.5 for Video Making: Creator's Showcase Thread (Coworker) (Melvin Vivas on X · notes), Coworker: free open-source desktop AI coworker app (Melvin Vivas on X · notes), Coworker: Open-Source Desktop App for AI Agents (Melvin Vivas on X · notes), Using Devin AI to Test the Coworker Desktop App on Windows (Melvin Vivas on X · notes) and 38 more

Try this

• Build a multi-agent video pipeline in Codex: one subagent each for b-roll search and download, music, voiceover, motion graphics, and a final review step.