Free forever · Installs in 30 seconds

Paste one line.
Cut your AI bill in half.

Most teams are overspending 40–60% on Claude, Cursor and Codex without knowing it. KostAI finds the waste in two minutes. Free. Nothing leaves your machine.

PASTE THIS into Claude Code, Cursor, or Cowork
$ npx -y @sapperjohn/kostai install

That's it. Your assistant installs KostAI, scans your setup, and shows you the exact dollar amount you're wasting each month. No login. No credit card.

✓ Runs on your machine ✓ Nothing uploaded ✓ MIT open source

How it works (really, this is all of it)

No dashboard to learn. No config to tune. You paste one line and you get a bill that's half the size.

📋
Step 1
Paste the line
Copy it above. Paste into Claude Code, Cursor, or Cowork chat. Press enter. Done talking.
🔎
Step 2
It scans — locally
KostAI looks at your AI calls on your own machine. Nothing is sent to us. Finishes in about 60 seconds.
💸
Step 3
You see the savings
One page. Plain English. "You're paying Opus to write git messages — that costs $X/month. Fix is five lines."
$266/day
Average savedmid-sized product teams
50%
Typical cutto Claude & Cursor bills
$0
Free plan foreverpaid is optional

Want the always-on brain? $5 a month.

We run a fleet of AI agents that costs us thousands every month — building, testing, and pushing continual improvements to your setup. You get all of it for $5.

Everything · $5/mo
$5/ month

Doubles your productivity. Saves you thousands. Cancel anytime.

  • ✓Always-on brain. Watches your AI stack 24/7 and auto-files fixes when it spots new waste.
  • ✓Continual improvements. A fleet of AIs (costing us thousands) keeps tuning your routing, caching, and prompts — you just get faster and cheaper each week.
  • ✓Everything free, plus BrainOfBrains. KostAI stays free forever. The $5 plan adds the bigger brain layer on top.
  • ✓Priority human help. Email us. A real person replies same day.
Start $5/mo →
Zero-risk promise: if KostAI doesn't save you at least 10× the $5 price in your first month, we refund the $5 and send you a detailed report anyway. We keep receipts.

Still here? Paste the line.

Free. 30 seconds. Nothing leaves your machine.

Take me back to the paste box ↑

Questions people ask

If you're not sure, click any of these.

Is my code leaving my machine?
No. KostAI runs entirely on your laptop. It looks at your AI usage logs locally and prints a report in your terminal. Nothing is uploaded anywhere. The code is MIT-licensed and on GitHub — you can read every line.
What is Claude Cowork? What do I paste it into?
Cowork is Anthropic's workspace where you chat with Claude. The one-liner also works in Claude Code, Cursor, Windsurf, or any coding assistant that can run shell commands. Just paste the line, press enter, and your assistant does the rest.
Why is it only $5 a month? What's the catch?
No catch. We run a fleet of AIs that costs us thousands every month to tune everyone's setup at once. Charging $5 × lots of teams pays for that fleet. You get improvements worth thousands for the price of a coffee. If it saves you less than $50 in month one, we refund you.
Does this work on Codex, Cursor, or Gemini too — not just Claude?
Yes. KostAI instruments any LLM call your project makes — Anthropic, OpenAI (Codex), Google (Gemini), local models. Most of the savings come from model routing (stop using the $$$ model for cheap tasks) and context bloat (stop sending 10,000 lines when 200 would do), and those exist everywhere.
What's the difference between KostAI and BrainOfBrains?
KostAI is free forever and finds the waste. BrainOfBrains ($5/mo) includes KostAI and adds the always-on brain that watches your whole stack continuously and auto-files improvements. Most people start with KostAI, see the savings, and flip to the $5 plan once they're convinced. See BrainOfBrains →