qwed-ucp 0.2.0

QWED verification for Universal Commerce Protocol (UCP) transactions

QWED-UCP

Verification for Universal Commerce Protocol (UCP) Transactions

QWED-UCP is a verification layer for Google's Universal Commerce Protocol, ensuring AI agent commerce transactions are mathematically correct.

Why QWED-UCP?

AI agents (like Gemini) are now handling e-commerce:

• Cart calculations
• Tax percentages
• Discount math
• Refunds

Problem: AI agents hallucinate on math.

Solution: QWED-UCP verifies every transaction deterministically.

The 3 Guards

Guard	Engine	Verifies
Money Guard	SymPy	Cart totals, tax, discounts
State Guard	Z3	Checkout state machine logic
Structure Guard	JSON Schema	UCP schema compliance

Installation

pip install qwed-ucp

Quick Start

from qwed_ucp import UCPVerifier

verifier = UCPVerifier()

checkout = {
    "currency": "USD",
    "totals": [
        {"type": "subtotal", "amount": 100.00},
        {"type": "tax", "amount": 8.25},
        {"type": "total", "amount": 108.25}
    ],
    "line_items": [...]
}

result = verifier.verify_checkout(checkout)

if result.verified:
    print("✅ Transaction verified - safe to process!")
else:
    print(f"❌ Verification failed: {result.error}")

Integration with UCP

# Middleware for UCP checkout
def ucp_checkout_middleware(checkout_json):
    verifier = UCPVerifier()
    result = verifier.verify_checkout(checkout_json)
    
    if not result.verified:
        raise UCPVerificationError(result.error)
    
    return proceed_to_payment(checkout_json)

Links

• Universal Commerce Protocol
• QWED Verification
• Google UCP Docs

License

Apache 2.0