claude-md-improver

CLAUDE.md Improver

Audit, evaluate, and improve CLAUDE.md files across a codebase to ensure Claude Code has optimal project context.

This skill can write to CLAUDE.md files. After presenting a quality report and getting user approval, it updates CLAUDE.md files with targeted improvements.

Workflow

Phase 1: Discovery

Find all CLAUDE.md files in the repository:

find . \( -name "CLAUDE.md" -o -name "CLAUDE.local.md" \) 2>/dev/null | head -50
find .claude/rules -name "*.md" 2>/dev/null

File Types & Locations:

Type	Location	Purpose
Project root	./CLAUDE.md	Primary project context (checked into git, shared with team)
Alternative location	./.claude/CLAUDE.md	Equivalent to project root CLAUDE.md
Local overrides	./CLAUDE.local.md	Personal/local settings (auto-gitignored, not shared)
Global defaults	~/.claude/CLAUDE.md	User-wide defaults across all projects
Package-specific	./packages/*/CLAUDE.md	Module-level context in monorepos
Subdirectory	Any nested location	Feature/domain-specific context
Rules (global)	./.claude/rules/*.md	Always loaded at launch (no paths frontmatter)
Rules (path-scoped)	./.claude/rules/*.md	Loaded only when Claude reads files matching paths frontmatter globs

Note: Claude walks up the directory tree from the current working directory, loading CLAUDE.md and CLAUDE.local.md at each level. Subdirectory CLAUDE.md files load on-demand when those directories are accessed.

Import syntax: CLAUDE.md files support @path/to/file imports to pull in external files. Imported files can chain imports up to 5 hops deep.

If no CLAUDE.md files are found, skip to Phase 2b to create one from scratch.

Phase 2a: Quality Assessment (Existing Projects)

For each CLAUDE.md file, evaluate against quality criteria. See references/quality-criteria.md for detailed rubrics.

Quick Assessment Checklist:

Criterion	Weight	Check
Commands/workflows documented	High	Are build/test/deploy commands present?
Architecture clarity	High	Can Claude understand the codebase structure?
Non-obvious patterns	Medium	Are gotchas and quirks documented?
Conciseness	Medium	No verbose explanations or obvious info?
Currency	High	Does it reflect current codebase state?
Actionability	High	Are instructions executable, not vague?

Size guideline: Target under 200 lines per CLAUDE.md file. Bloated files cause Claude to ignore instructions. If a file exceeds this, recommend splitting into .claude/rules/*.md or using @path imports.

Quality Scores:

• A (90-100): Comprehensive, current, actionable
• B (70-89): Good coverage, minor gaps
• C (50-69): Basic info, missing key sections
• D (30-49): Sparse or outdated
• F (0-29): Missing or severely outdated

Phase 2b: Bootstrap (New Projects)

When no CLAUDE.md exists, analyze the codebase to generate one:

1. Scan the project — identify package manager, build system, test framework, directory structure, and entry points
2. Select a template from references/templates.md matching the project type (minimal, comprehensive, monorepo, or package)
3. Fill the template with real commands, paths, and patterns discovered from the codebase
4. Present the draft to the user for review before writing

After user approval, create ./CLAUDE.md using the Write tool. Then proceed to Phase 3 to output a quality report on the newly created file.

Phase 3: Quality Report Output

ALWAYS output the quality report BEFORE making any updates.

Format:

## CLAUDE.md Quality Report

### Summary
- Files found: X
- Average score: X/100
- Files needing update: X

### File-by-File Assessment

#### 1. ./CLAUDE.md (Project Root)
**Score: XX/100 (Grade: X)**

| Criterion | Score | Notes |
|-----------|-------|-------|
| Commands/workflows | X/20 | ... |
| Architecture clarity | X/20 | ... |
| Non-obvious patterns | X/15 | ... |
| Conciseness | X/15 | ... |
| Currency | X/15 | ... |
| Actionability | X/15 | ... |

**Issues:**
- [List specific problems]

**Recommended additions:**
- [List what should be added]

#### 2. ./packages/api/CLAUDE.md (Package-specific)
...

Phase 4: Targeted Updates

After outputting the quality report, ask user for confirmation before updating. See references/update-guidelines.md for detailed guidance on what to add and what to avoid.

Update Guidelines (Critical):

1. Propose targeted additions only - Focus on genuinely useful info:

   • Commands or workflows discovered during analysis
   • Gotchas or non-obvious patterns found in code
   • Package relationships that weren't clear
   • Testing approaches that work
   • Configuration quirks

2. Keep it minimal - Avoid:

   • Restating what's obvious from the code
   • Generic best practices already covered
   • One-off fixes unlikely to recur
   • Verbose explanations when a one-liner suffices

3. Show diffs - For each change, show:

   • Which CLAUDE.md file to update
   • The specific addition (as a diff or quoted block)
   • Brief explanation of why this helps future sessions

Diff Format:

### Update: ./CLAUDE.md

**Why:** Build command was missing, causing confusion about how to run the project.

```diff
+ ## Quick Start
+
+ ```bash
+ npm install
+ npm run dev  # Start development server on port 3000
+ ```

### Phase 5: Apply Updates

After user approval, apply changes using the Edit tool. Preserve existing content structure.

## Templates

See [references/templates.md](references/templates.md) for CLAUDE.md templates by project type.

## Common Issues to Flag

1. **Stale commands**: Build commands that no longer work
2. **Missing dependencies**: Required tools not mentioned
3. **Outdated architecture**: File structure that's changed
4. **Missing environment setup**: Required env vars or config
5. **Broken test commands**: Test scripts that have changed
6. **Undocumented gotchas**: Non-obvious patterns not captured

## User Tips to Share

When presenting recommendations, remind users:

- **Keep it concise**: CLAUDE.md should be human-readable; dense is better than verbose
- **Actionable commands**: All documented commands should be copy-paste ready
- **Use `CLAUDE.local.md`**: For personal preferences not shared with team (auto-gitignored)
- **Global defaults**: Put user-wide preferences in `~/.claude/CLAUDE.md`

## What Makes a Great CLAUDE.md

See [references/templates.md](references/templates.md) for key principles, recommended sections, and templates by project type.