Greptile uses GPT-6 Astra computer use to run each PR's app and click through it like a user
In an Oct 26 OpenAI case study, Greptile says its review agent now starts a dev server for a pull request, resizes the browser to an iPhone viewport and walks the app to catch bugs code reading misses, like a button that vanishes on mobile. It also feeds its codebase Knowledge Base to Codex over MCP, which it says cuts how often AI-written code gets reverted.