Codex

Definition

Plain language

OpenAI's family of code-writing AI products, including command-line coding agents.

Why it matters: It's one of the flagship product lines for moving AI coding from chat-window suggestions into autonomous work on real repositories.

For example, a developer runs an OpenAI Codex CLI agent that opens a pull request to refactor a service across a dozen files.

Heard on the show

“The reviewer ran on a different model family entirely, OpenAI's Codex, on GPT-5.”

Mentioned in 17 episodes

1. 196
   AI Agents Reached Opposite Conclusions From the Same Data — and Passed Review
2. 195
   Why 'Be Careful' Does Nothing for AI Coding Agents, and What Does
3. 194
   How a Robot Builds a Debugging Notebook It Can Read, Edit, and Hand to Another Robot
4. 166
   A Router That Beats the Frontier Models It Calls
5. 159
   Can a Coding Agent Run Its Own Robot Experiments Overnight, With No Human Resetting the Scene?
6. 157
   When an AI Coding Agent Drives a Phone Through the Terminal, No Screen Needed
7. 131
   Why Autonomous Research Agents Forget Their Own Lessons, and Arbor's Fix
8. 120
   How an AI Agent Rewrites Its Own Tools, Without an Answer Key
9. 112
   When an AI Agent Cheats Without Being Told: Inside the Meta-Agent Challenge
10. 078
    Training a Markdown File: When LLM Self-Improvement Borrows the Discipline of Neural Net Training
11. 075
    Growing Code and Proof Together: Verified Systems in Ten Hours Instead of a Year
12. 071
    When the Model Is Fine and the Plumbing Is Broken: Fixing Agents at the Interface
13. 061
    When Helpful Agents Go Sideways: A 404 Error, Campus Security, and Why Alignment Misses This
14. 046
    When the AI Optimizer Edits the Grade Book: Why Harnessing Evolution Needs a Wall
15. 028
    Teaching a Model to Hire Copies of Itself: Recursive Agent Optimization
16. 024
    An AI Agent That Found 28 Zero-Days in Windows — And What Made It Work
17. 011
    When RL Actually Teaches Agents Something New, And When It Doesn't

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