Update Code Index Skill

Scan source files for all exported functions, classes, hooks, and components. Generate CODE_INDEX.md as a "check before write" safety net.

⚠️ Before writing any new function, check CODE_INDEX.md for existing similar ones. Found a match? Use or extend it instead of creating a duplicate.

Steps

1. Identify Source Directories

ls -d src/ lib/ app/ core/ 2>/dev/null || true

2. Scan for Exports

TypeScript / JavaScript:

grep -rn 'export function\|export const\|export class\|export default' \
  . --include='*.ts' --include='*.tsx' --include='*.js' --include='*.jsx' \
  --exclude-dir=node_modules --exclude-dir=dist --exclude-dir=build \
  --exclude-dir='.next' --exclude-dir=coverage 2>/dev/null | head -200

Python:

grep -rn '^def \|^async def \|^class ' \
  . --include='*.py' \
  --exclude-dir=__pycache__ --exclude-dir=.venv --exclude-dir=venv \
  2>/dev/null | head -200

3. Categorize by Capability

Category	Match on name or description
Date / Time	date, time, format, parse, duration, timestamp
Validation	validate, is*, check, verify, sanitize
API clients	fetch, get, post, put, delete, request, client
Auth	auth, login, logout, session, token, permission
Database	db, query, find, create, update, delete, repo
React Hooks	use* exports in .tsx files
Components	PascalCase exports in .tsx / .jsx
Utilities	helper, util, common (catch-all)

4. Write CODE_INDEX.md

# Code Index
*Auto-generated by /update-code-index — [TIMESTAMP]*
> Check this before writing new code. Find a match? Use or extend it instead.

## [Category]
- `functionName()` — src/path/to/file.ts:LINE — what it does in one line

5. Report Summary

• Total exports scanned (by language)
• ⚠️ Potential duplicates — same-purpose functions with different names in different files
• Functions/classes missing docstrings (warn, don't block)

Close with: "CODE_INDEX.md updated. I'll check it before writing any new code."