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Codex performed exhaustive QA testing on the onboarding flow, surfacing 11 issues including one high-severity blocker, with a Google Sheet of screenshots.
Codex did exhaustive automated QA testing that a human would skip, catching real bugs. ✦ AI generated
Claire Vo · Lenny's Newsletter · 2026-07-22 · original ↗
How I use Codex to QA my onboarding flow, including exhaustive mobile testing I would never do manually... Results: 11 issues, one high-severity blocker, one Google Sheet with screenshots
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Browser use and computer use via Codex (ChatGPT desktop app) is a daily driver for both personal and professional workflows, not just a novelty feature.Claire Vo · Lenny's Newsletter · conf 90%Under-prompting frontier models — giving goals rather than detailed step-by-step instructions — produces better results because it forces the model to reason through the problem rather than mechanistically follow a script.Claire Vo · Lenny's Newsletter · conf 85%