Stop AI from Suggesting Deprecated Libraries in 5 Minutes

Problem: AI Keeps Suggesting moment.js and Other Dead Libraries

Your AI assistant suggests moment.js for dates, request for HTTP calls, or node-sass for styling—all deprecated years ago. You waste time debugging obsolete code.

You'll learn:

• Why AI models recommend outdated packages
• How to add context that prevents this
• Which libraries to watch for in 2026

Time: 5 min | Level: Beginner

Why This Happens

AI models trained on historical code see deprecated libraries used frequently in older projects. Without explicit instructions, they default to patterns from their training data (often 2021-2023 code).

Common symptoms:

• Suggestions for moment.js instead of native Temporal or date-fns
• create-react-app instead of Vite
• node-sass instead of sass (Dart Sass)
• Packages with npm deprecation warnings

Solution

Step 1: Add Context to Your Prompts

For any AI assistant (Copilot, Claude, ChatGPT):

Before suggesting libraries:
- Check if packages are actively maintained (npm last publish < 6 months)
- Avoid deprecated packages (moment.js, request, node-sass, CRA)
- Prefer native APIs when available (Fetch over axios, Temporal over date libraries)
- Use Vite/Next.js instead of create-react-app

Where to put this:

• GitHub Copilot: Add to .github/copilot-instructions.md in your repo root
• Claude: Include in your project's README.md or initial message
• ChatGPT/Cursor: Paste at the start of coding sessions

Step 2: Create a Project Blocklist

# .ai-preferences.yml (or in README)
deprecated_packages:
  - moment        # Use: date-fns, Temporal API, dayjs
  - request       # Use: native fetch, axios, got
  - node-sass     # Use: sass (Dart Sass)
  - gulp          # Use: npm scripts, Vite
  - bower         # Use: npm, pnpm
  - create-react-app  # Use: Vite, Next.js

prefer_modern:
  dates: "Temporal API (native) or date-fns"
  http: "fetch (native) or undici"
  build: "Vite or esbuild"
  css: "Tailwind CSS or vanilla CSS modules"

Reference this file when asking for code: "Check .ai-preferences.yml before suggesting packages."

Step 3: Verify Suggestions with npm

# Check if a package is maintained
npm view <package-name> time.modified

# Example
npm view moment time.modified
# Returns: 2022-07-07 (not maintained)

npm view date-fns time.modified  
# Returns: 2024-12-15 (actively maintained)

If last update is >12 months old: Ask AI for alternatives.

Step 4: Set AI Tool Configurations

GitHub Copilot (VS Code):

Create .github/copilot-instructions.md:

# Copilot Instructions

## Package Selection Rules
1. Never suggest: moment, request, node-sass, create-react-app
2. For dates: Use Temporal API (Node 22+) or date-fns
3. For HTTP: Use native fetch or undici
4. For React: Use Vite or Next.js starter
5. Check npm "last publish" before suggesting (must be <6 months)

## Project Context
- Node.js: 22+
- TypeScript: 5.5+
- React: 19+

Cursor/Windsurf:

Add to cursor_rules or project instructions:

@Modern Stack Rules
- Use ESM imports only
- Prefer native APIs (fetch, Temporal)
- No deprecated packages (see .ai-preferences.yml)
- Suggest pnpm over npm

Verification

Test it:

Ask your AI: "Add date formatting to this React component"

You should see:

• ✅ date-fns or native Intl.DateTimeFormat
• ✅ Temporal.Now (if Node 22+)
• ❌ NOT moment.js

If it still suggests moment:

• Add "Don't use moment.js" to your prompt
• Reference your .ai-preferences.yml file
• Specify the year: "Using 2026 best practices..."

Common Deprecated Packages in 2026

What You Learned

• AI models default to patterns from older training data
• Explicit context in prompts prevents outdated suggestions
• Project-level instruction files guide AI tools consistently
• Always verify package maintenance status before using

Limitations:

• AI might still suggest deprecated packages if they're in your existing codebase
• Some tools don't support instruction files (use prompts instead)

Quick Reference: AI Context Template

Copy this into your prompts:

Context for AI Assistant:
- Year: 2026
- Node.js: 22+ (native fetch, Temporal API available)
- Avoid: moment, request, node-sass, create-react-app
- Prefer: Native APIs > Modern maintained packages > Deprecated tools
- Check npm last publish date before suggesting

Tested with GitHub Copilot, Claude Code, ChatGPT o1, Cursor 0.43 - February 2026