# Answer key — Exercise 4

The reveal for "Trim the context" lives in
**[`claude-md-trim.md`](claude-md-trim.md)**, in this directory: the six lines
that must survive with the mistake each one prevents, the four classic false
keeps, the reference trimmed `CLAUDE.md` at fifteen lines, and the reference
`.claude/rules/formatting.md` with its frontmatter.