Most "add AI to your game" tutorials assume you'll sign up for OpenAI with a credit card, host a proxy, and eat per-token bills in dollars. But a Roblox game earns Robux, not dollars — and plenty of Roblox devs are teenagers without a card at all.
Here's the mismatch nobody addresses: your revenue is Robux, your AI bill is USD, and the two don't meet.
Pay for AI the same way your game earns
Cortex is built for this: you pay in Robux via a game pass, no card. The API key never leaves your server, and you're billed on output tokens only — the system prompt, memory, and chat history you resend on every call are free, and repeated replies are cached for nothing.
local Cortex = require(game.ServerStorage.Cortex)
local ai = Cortex.new("YOUR_KEY")
print(ai:ask("You are a gruff blacksmith. One line.", "forge me a sword?"))
That's the whole integration — one function, one server-side request, and it works for NPCs, quests, item text, and chat moderation.
It's OpenAI-compatible, so if you ever outgrow it you point your SDK somewhere else and only the address and key change.
Free open beta, keys in the Discord: https://discord.gg/A3MSqwkvn7 · kit: https://github.com/cortex-rbx/roblox-ai-kit
