Codex checks its work for you

Javi walks through a logging refactor and shows why Codex's self-verification is a step change: the model runs the app, finds the right session, and proves logs still flow. Takeaways: - Codex can validate its work by running tests and launching the app. - It excels at broad refactors that touch many files. - The model can find session IDs and query tools on its own. - Verification collapses a risky manual loop into minutes. When the agent can prove correctness, you can move faster with less risk. Chapters: 00:00 Why Codex has been a step change 00:18 Self-verification: run tests and launch the app 00:52 The task: a logging refactor across many files 01:10 The risk: do not break observability 01:28 How this used to be verified manually 01:35 Ask the model to verify logs end-to-end 01:50 It finds the session ID and queries logs MCP 02:03 Proof: logs still pipe, task done fast