Claude Code went from research preview to a meaningful share of all public GitHub commits surprisingly fast, per Anthropic's own data and the broader best-practices roundup . Most of those commits shipped to production. A meaningful share rolled back soon after. The interesting question is not how the model writes the code. It is what happens in the early window before it starts. That window is where good Claude Code sessions and bad ones diverge. The Cold-Start Problem A fresh Claude Code session has no idea what you decided earlier, what the codebase looks like, what the current state of any library you depend on actually is, or what mistakes you already made and ruled out. Without help, it rebuilds your reasoning from scratch every time. Usually wrong. Three failure modes show up almost immediately. The model invents class names that sound plausible but do not exist in the project. It cites API methods from versions of an SDK that got renamed two releases ago.…