---
type: skill
lifecycle: stable
inheritance: inheritable
name: doc-hygiene
description: Documentation hygiene — anti-drift rules, count elimination, and living document maintenance
tier: standard
applyTo: '**/*doc*,**/*hygiene*'
currency: 2026-04-20
lastReviewed: 2026-04-30
---

# Documentation Hygiene


> Prevent documentation drift through structural rules — not manual vigilance.

## The Count Problem

Hardcoded counts (e.g., "109 skills", "28 instructions", "6 agents") in prose become stale within days during active development. Every count is a future bug.

### Rules

| Rule | Do | Don't |
|------|----|-------|
| **No counts in prose** | "See the skills catalog for the current list" | "the AI assistant has 109 skills" |
| **Counts in tables OK** | Tables with `| Count | Value |` format are scannable and updatable | Counts buried in paragraphs |
| **Single source of truth** | One canonical location per metric | Same count in 5 files |
| **Link, don't copy** | "See brain-health-grid for current list" | Duplicate the list inline |
| **Timestamp proximity** | Counts near a "Last Updated" date are acceptable | Undated counts |

### Canonical Sources

The filesystem is always the source of truth. Derive counts from directories, not from prose.

| Metric | Canonical Source | Why |
|--------|-----------------|-----|
| Skill count | `.github/skills/` directory count (or generated catalog if present) | Filesystem is truth |
| Instruction count | `.github/instructions/` directory listing | Filesystem is truth |
| Prompt count | `.github/prompts/` directory listing | Filesystem is truth |
| Agent count | `.github/agents/` directory listing | Filesystem is truth |
| Muscle count | `.github/muscles/` directory listing | Filesystem is truth |
| Command count | `package.json` `contributes.commands` (if applicable) | Code is truth |
| Connection count | Brain QA validation output | Validated at runtime |

### Acceptable Count Locations

Counts are **tolerated** (not encouraged) in these specific locations because they serve as dashboards:

| File | Purpose | Update Cadence |
|------|---------|----------------|
| `copilot-instructions.md` Memory Stores table | AI working context | Per release |
| `README.md` architecture tree | User-facing overview | Per release |

All other files should use **descriptive references** instead of counts.

## Document Freshness

### Staleness Indicators

| Signal | Action |
|--------|--------|
| Count doesn't match filesystem | Fix count or replace with reference |
| "Last Updated" older than 30 days on living doc | Review for accuracy |
| Version number doesn't match current release | Update or archive |
| References to removed/renamed files | Fix or remove reference |

### Living vs Historical Documents

| Type | Examples | Count Policy |
|------|----------|-------------|
| **Living** | README, copilot-instructions, ROADMAP, USER-MANUAL | Minimize counts; keep current |
| **Historical** | Research papers, competitive analyses, archived docs | Counts are snapshots — leave as-is |
| **Generated** | brain-health-grid output | Counts are output of audit — OK |

## Docs-as-Architecture

Documentation in a cognitive architecture IS architecture. Apply the same engineering rigor to docs that you would to code:

| Code Concept | Docs Equivalent |
|-------------|-----------------|
| Broken import | Broken cross-reference link |
| Stale dependency | Stale count or version number |
| Orphan module | File not linked from any index |
| Circular dependency | Two files claiming to be source of truth |
| Dead code | Archived content still linked from living docs |

**Principle**: If a doc change would break another doc's accuracy, it's a breaking change. Treat it as such.

## Link Integrity

### Rules

| Rule | Enforcement |
|------|-------------|
| Every markdown link in living docs must resolve | Grep + verify during audit |
| Every important file in a folder should be linked from its `README.md` | Orphan check |
| Moving a file requires updating ALL references in the same commit | Grep for filename in all .md files before moving |
| Archived docs removed from active indexes | Don't link to `archive/` from living docs |
| Use relative paths within doc trees | `./architecture/FILE.md` not absolute paths |

### Link Integrity Checker

```bash
# Find all markdown links and verify they resolve
find . -name "*.md" -exec grep -oP '\[.*?\]\((?!http)[^)]+\)' {} + | while read match; do
  file=$(echo "$match" | sed -E 's/.*\(([^)]+)\).*/\1/')
  dir=$(dirname "$match" | cut -d: -f1)
  target="$dir/$file"
  if [ ! -f "$target" ] && [ ! -d "$target" ]; then
    echo "BROKEN: $match"
  fi
done
```

```typescript
// Programmatic link integrity check
import { glob } from 'glob';
import { readFile } from 'fs/promises';
import { dirname, resolve, existsSync } from 'path';

async function checkLinkIntegrity(docsRoot: string): Promise<string[]> {
  const broken: string[] = [];
  const mdFiles = await glob(`${docsRoot}/**/*.md`);
  
  for (const file of mdFiles) {
    const content = await readFile(file, 'utf-8');
    const linkRegex = /\[.*?\]\((?!http)([^)]+)\)/g;
    let match;
    
    while ((match = linkRegex.exec(content)) !== null) {
      const linkPath = match[1].split('#')[0]; // Remove anchors
      const absolutePath = resolve(dirname(file), linkPath);
      
      if (!existsSync(absolutePath)) {
        broken.push(`${file}: ${match[0]} -> ${absolutePath}`);
      }
    }
  }
  
  return broken;
}
```

### Orphan Detection

A file is orphaned if it exists in a doc folder but is not referenced by any index or parent document. Orphans are either:

- **Forgotten knowledge** → add to appropriate index
- **Stale artifacts** → archive or delete