HOW CLAUDE CODE BUILDS A SYSTEM PROMPT

Summary from the TLDR newsletter

System prompts are often the best manual for how an app is intended to work. The accidental leak of Claude Code's source code reveals how Claude Code assembles a context and shows how complex context engineering can be, and the importance of harnesses. This post contains a table that shows how Claude Code assembles a system prompt. Some components are always included, while others are conditional, and components may have variations.