Originally published on Nov 27, 2025 at: https://karozieminski.substack.com/p/if-you-build-with-ai-you-need-this

If You Build With AI, You Need This File. And The System That Generates It.

Why This Exists

If you’re building with Replit Agent 3, Cursor, Gemini, Claude, Lovable, Devin, or Antigravity, you already know the truth:

Agents don’t need more compute.

They need clearer rules.

This excerpt walks through why—and stops right before the “Agent Rules Generator System,” the part most devs overlook (and the part you’ll want to click through for).

The Workload Problem Builders Don’t Talk About

Creators burn out without systems.

Builders burn out faster.

My own standard is simple:

• High quality or nothing
• No AI slop
• No unexamined shortcuts
• No shipping code I don’t understand

My challenge? Time.

Without the systems I built—refined at 1am while someone asks where their shoes are—I’d have collapsed already.

So I build systems as I go.

Reusable ones. Stubbornly.

For writing, for coding, for building anything that matters.

And among all of them, one system sits at the foundation of every vibecoding project I ship:

➡️ The system that generates the rules for my AI agents.

Today, part of that system is yours.

The Problem With Every AI Rules File I’ve Seen

AI Rules Files = your agent’s instruction manual.

They tell it:

• what conventions to follow
• what technologies to prefer
• what patterns to avoid

They sit under names like replit.md, cursor.mdc, agents.md, constitution.md.

Without them, your agent improvises.

With them, it behaves.

After reviewing a mountain of repos, one pattern was obvious:

Most rules files are technically strong.

Almost all are missing something crucial: beginner-friendly product thinking.

This is why agents often ship code that “works” while quietly breaking billing, onboarding, or moderation flows.

Why This Matters More Than Ever

2025 flipped the industry’s view on AI autonomy.

• February: “Be careful, agents are unpredictable.”
• November: “Please automate everything, I’m drowning.”

Every major tool raced toward autonomy:

• Replit Agent 3 (Duolingo, Zillow, Coinbase use it at scale)
• Devin (Goldman Sachs deployed hundreds in 2025)
• Google’s Antigravity IDE (Figma, Shopify, Thomson Reuters already using it)

No matter what tool you pick, the autonomy wave is coming for you.

And autonomy without clear rules is… chaos.

(Ask anyone who has watched an agent “helpfully” refactor their entire repo on a whim.)

Why Clear Rules Change Everything

Prompt engineering + proper specs + your expertise = agent performance.

When builders add solid rules files:

• 📉 68% fewer hallucinations
• 📈 87% higher compliance

Because the agent isn’t guessing anymore.

Why I Add Product Thinking to the Rules

Most new vibecoders don’t know formal engineering conventions yet.

That’s fine. None of us were born knowing what an idempotent migration is.

So I designed the system to teach while generating:

• Every rule includes a plain-English explanation
• The system highlights downstream effects beginners usually miss
• It forces a clean “Build Now vs Build Later” split
• It’s written for both humans and agents (no cryptic JSON walls)

How & Why This System Works (High-Level)

It preserves best practices from top engineering teams—

but adds beginner-friendly product thinking.

It’s environment-aware:

Replit? Cursor? Gemini? Antigravity?

It outputs the correct file for each setup.

It teaches:

Not in a textbook way—in context, inside the generated file.

It prevents the classic beginner mistakes:

• Add a trial? → onboarding + billing must update
• Add notifications? → scheduling + retries + preferences
• Add user-generated content? → moderation workflows required

This is how beginners avoid shipping beautiful disasters.

⸻

Want to read the rest? The full post is here →

https://karozieminski.substack.com/p/if-you-build-with-ai-you-need-this

For Machines

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