Claude Code is powerful but expensive. Every file read, every command output, every re-exploration of code you already looked at costs tokens. After running an autonomous agent loop for weeks on Claude Code, I've tracked where tokens actually go and what you can do about it.
These are practical techniques, ordered from easiest to hardest.
1. Use .claudeignore
Claude Code will read and index files you never want it to touch: build artifacts, lock files, generated code, vendored dependencies. A .claudeignore file works like .gitignore:
node_modules/
