Your UCP agent passes conformance. It still pays the wrong amount.

Short summary

UCP conformance testing verifies JSON message format but misses critical agent behavior failures in production: wrong payment calculations, phishing vulnerabilities, forged response handling, unsafe OAuth linking, unauthorized payment methods, and account data leakage. spck.dev introduces behavior-focused testing against adversarial stores with kill-rate validation to catch these catastrophic bugs before they cost money.

• •Conformance testing only validates JSON schema—99% of stores score A-grade yet many still fail in practice
• •Six critical failure modes (miscalculated totals, phishing, forged responses, unsafe linking, unauthorized payments, data leaks) pass conformance but are production-breaking
• •spck.dev offers adversarial behavioral testing with kill-rate validation, not just schema compliance

Generated with AI, which can make mistakes.