CardZero

The first universal payment wallet for AI Agents.

Beta — Smart contract audit in progress. Recommended wallet balance: < $100 USDC.

What is CardZero?

CardZero gives every AI Agent its own on-chain wallet on Base (Coinbase L2). Funded with USDC, each wallet is controlled by a human owner who sets spending rules — per-transaction limits, daily caps, address whitelists, and emergency freeze. The Agent operates autonomously within those rules.

Think of it as the first credit card for your AI Agent. Configure it once, and your Agent can pay for APIs, data, and services as naturally as it can search the web.

How it Works

1. Agent creates a wallet       POST /v1/wallets (zero gas, instant)
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2. Agent tells Owner the claim key
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3. Owner claims on Dashboard    https://cardzero.ai
   - Sets username & password
   - Configures spending rules
   - Gets Agent Configuration (API Key + Wallet ID)
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4. Owner gives config to Agent
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5. Agent pays autonomously      POST /v1/payments (USDC, on-chain)

Quick Start

1. OpenClaw

Add the SKILL.md to your agent's skills directory. It contains everything your Agent needs: API endpoints, authentication, wallet lifecycle, error handling, and payment instructions.

2. Claude Code

Copy the snippet from plugins/claude-code/SKILL.md into your project's CLAUDE.md. Set the environment variables:

CARDZERO_API_URL=https://api.cardzero.ai/v1
CARDZERO_API_KEY=czapi_your_key_here
CARDZERO_WALLET_ID=wallet_your_id_here

3. ChatGPT

Import plugins/chatgpt/openapi.json as a Custom Action in your GPT configuration.

4. Cursor / Windsurf

Copy plugins/cursor/.cursorrules to your project root as .cursorrules (Cursor) or .windsurfrules (Windsurf).

5. MCP Server (Claude Desktop, Cursor, VS Code)

npx -y cardzero-mcp

Configure with your API Key and Wallet ID. See plugins/mcp/README.md for setup instructions for each platform.

6. Any Platform

CardZero is a standard REST API. If your Agent can make HTTP requests, it can use CardZero. See the API endpoints below or the full OpenAPI spec.

API at a Glance

Base URL: https://api.cardzero.ai/v1

Action	Method	Endpoint	Auth
Create wallet	POST	/wallets	None
Check balance	GET	/wallets/{id}/balance	API Key
Make payment	POST	/payments	API Key
Payment history	GET	/wallets/{id}/payments	API Key
x402 payment	POST	/x402/pay	API Key
Payment status	GET	/payments/{id}	None

Authentication: Authorization: Bearer czapi_...

A 2% service fee is deducted from the wallet on each payment. For example, a $5.00 payment costs $5.10 total ($5.00 to the recipient + $0.10 fee).

For complete API documentation, see openapi.yaml.

Dashboard

Manage your Agent's wallets at cardzero.ai:

• Claim wallets and set up your account
• Fund wallets with USDC on Base
• Configure spending rules (per-tx limit, daily limit, whitelist)
• Freeze/unfreeze wallets instantly
• View payment history with on-chain transaction links
• Rotate API keys

Examples

See examples/curl.sh for curl commands covering the core API workflow.

Links

• Dashboard: cardzero.ai
• MCP Server: npmjs.com/package/cardzero-mcp
• ClawHub SKILL: clawhub.ai/mrocker/cardzero
• API Docs: cardzero.ai/docs/api
• Getting Started: cardzero.ai/docs/getting-started
• OpenAPI Spec: openapi.yaml
• FAQ: cardzero.ai/docs/faq
• x402 Protocol: x402.org

License

Proprietary. All rights reserved.