x402 Protocol

PAYMENT
CARDS FOR
AI AGENTS

Issue cards. Set limits. Let your AI pay.

THE PROBLEM

Giving AI your wallet is dangerous

01

No Spending Limits

One rogue agent can drain your entire wallet in minutes

02

Manual Approval

MCP and browser extensions require you to click "approve" for every payment

03

No Control

Can't limit who your agent pays or how much it spends per day

THE SOLUTION

Give your AI a payment card, not your wallet

ISSUE
CARDS

16-digit card number, expiry date, just like a real credit card. Create as many as you need.

SET
LIMITS

Per-transaction cap, daily budget, total allowance. You decide how much your AI can spend.

FREEZE
ANYTIME

Pause or revoke any card instantly. One click to stop all payments.

GET STARTED →

Create your first payment card in minutes

HOW IT WORKS

Four steps.
Full control.

01

Create a card

Set spending limits, daily budget, and recipient whitelist

02

Give your AI the Payment Key

A simple API key that lets your agent request payment signatures

03

AI encounters HTTP 402

Agent calls 402ok with payment requirements, we check limits and sign if approved

04

Payment complete

Allowance deducted, transaction logged, AI gets the resource it paid for

x402 Standard

Built on the open x402 protocol for machine-to-machine HTTP payments. Learn more at x402.org

WHY 402OK

Cards vs Wallets

Spending Limits

Raw Wallet: No limits. Agent can spend everything in one transaction.

402ok Card: Per-tx limit, daily cap, and total allowance. Triple protection.

Recipient Control

Raw Wallet: Agent can pay anyone, anywhere, for anything.

402ok Card: Whitelist specific recipients. Block everything else.

Kill Switch

Raw Wallet: Once compromised, funds are gone. No way to stop it.

402ok Card: Pause or revoke instantly. Your funds stay safe.

Think of it like corporate cards

You don't give employees your bank account. You give them company cards with spending limits. Same idea for AI agents.

FEATURES

Everything you need
to stay in control

MULTI-CARD MANAGEMENT

Create unlimited cards for different agents
16-digit card numbers, color themes
Set expiry dates for temporary access
Pause, resume, or revoke anytime

SPENDING CONTROLS

Per-transaction limit
Daily spending cap
Pre-funded allowance balance
Global account limits

RECIPIENT WHITELIST

Specify allowed payment recipients
Block all unauthorized addresses
Update whitelist anytime
Per-card recipient controls

TRANSACTION HISTORY

Complete payment logs
See approved and denied requests
Filter by card, date, status
Export for accounting
USE CASES

One card per agent.
Full visibility.

AI Assistants

Claude, ChatGPT, custom agents. Give each one a card with a $10/day limit.

Backend Services

Cron jobs, data pipelines, automation scripts. Headless? No problem.

API Consumption

Pay-per-call APIs, premium data sources. Budget by project or client.

FAQ

Common questions

What is a Payment Card in 402ok?

It's a virtual card you issue to an AI agent. Each card has a 16-digit number, expiry date, spending limits, and a Payment Key (API key) that lets the agent request payment signatures.

How is this different from giving AI my wallet?

Your wallet has no limits. A card has per-transaction caps, daily limits, allowance budgets, and recipient whitelists. If an agent goes rogue, it can only drain the card's allowance—not your whole wallet.

What is "allowance"?

Allowance is the pre-funded balance on a card. You add funds to the allowance, and each payment deducts from it. When it hits zero, the card stops working until you top up.

Can I limit who my agent pays?

Yes. Each card has a whitelist. Add specific wallet addresses, and the card will only pay those recipients. All other payment requests are blocked.

What happens if I pause a card?

All payment requests using that card's Payment Key are immediately rejected. You can resume anytime, or revoke permanently.

Which blockchains are supported?

Base, X Layer, and more coming. We use USDC for payments via the x402 protocol.

How are private keys handled?

We use HD wallet derivation. Your master seed generates unique addresses, and private keys are derived at runtime—never stored in the database.

Do you support MCP?

Yes! We have an MCP endpoint for Claude and other MCP-compatible clients. But our HTTP API works with any client that can make REST calls.

What does 402ok cost?

Pricing details coming soon. Our goal: simple, transparent, pay-for-what-you-use.

START NOW

Create your first payment card for AI in minutes.

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