What you'll learn

Claude Code loads far more into its context window than the prompts you type: system context, CLAUDE.md files, tool definitions, file contents, and every turn of conversation history. Left unmanaged, the window fills, quality drifts, and costs climb. This course treats that window as something you engineer. Cost and accuracy get demystified: how the window actually fills, what tokens cost, how caching changes the math, and why long sessions degrade. Control comes from a small set of deliberate moves: compaction and clearing, the stable context every session inherits through CLAUDE.md, scoped rules, hooks, and the memory that persists after sessions end. With knowledge from this course, your extended Claude Code sessions stay accurate, predictable, and affordable because you decided what Claude sees.