SumatraPDF is a Windows GUI application for viewing PDF, ePub and comic books written in C++. Lately I do a lot of my SumatraPDF coding with AI agents: Claude Code, Grok Build, OpenAI Codex. They're good at writing code. They're less good at knowing if the code works, especially for GUI apps. ## The problem: agents don't drive UI well Say I ask an agent to fix a bug in PDF text search, or in the new feature that translates selected text via an LLM. How does the agent verify the fix? Sur...

Read the original article