Field Guide 28: a CLAUDE.md template with a size budget and 28 rules for what belongs in it and what belongs in path-scoped rules, skills or hooks instead, checked against the Claude Code memory docs. The kit adds a zero-dependency linter with 16 rules (size, required sections, @imports, stale paths and npm scripts, secrets, vague and dated wording), a filled-in example for the Acme UI design system that imports a shared AGENTS.md, and a bad example that fails with 10 errors and 14 warnings.
When Claude keeps ignoring rules that are in CLAUDE.md, when the file has grown past a screen or two, or before you share one repository's setup with a team or with other coding agents.