Free cheat sheet

.claude/rules cheat sheet: stop bloating CLAUDE.md

Per-folder rules that only load when Claude touches matching files.

claude-codecontext verified 26 Oct 2026

Why bother

The docs recommend keeping each CLAUDE.md under 200 lines. Long files cost context and Claude follows them less well. A rule with paths only loads when Claude reads, writes or edits a matching file.

Step 1: one file per topic

Create the file inside the rules folder. One topic per file.

.claude/rules/api-design.md

Step 2: scope it with paths

Add this frontmatter at the top. Need more patterns? Add more lines. A rule without paths always loads.

Trap 1: broken YAML

Invalid frontmatter makes the rule load as if it had no paths.

Watch out: Debug with claude --debug.

Trap 2: compaction

Rules with paths can be summarised away when the conversation compacts.

Watch out: A rule that must always stay? Drop paths, or move it back to the root CLAUDE.md.

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