FST Pay: Deterministic Safety-Gated Architecture for Youth Digital Payments
FST Pay proposes a deterministic safety-gated architecture for teen digital payments, pairing invariant authorization checks with decoupled post-settlement AI explanations.
Researchers propose FST Pay, a formal architecture for adolescent digital payments on rails like UPI that applies six deterministic invariant checks (spending limits, guardian co-sign policies, amount thresholds, merchant category codes, temporal intervals, hardware integrity) to classify transactions as ALLOW, REVIEW, or BLOCK. High-risk transactions trigger an asynchronous guardian co-sign workflow. Generative AI is restricted to post-settlement natural-language insights and holds no mutation privileges over the ledger, avoiding non-determinism on the real-time authorization path.
- Six deterministic invariant checks gate real-time payment authorization
- ALLOW/REVIEW/BLOCK outcomes via mutually exclusive decision function
- Guardian co-sign workflow triggered for high-risk transactions
- Generative AI limited to post-settlement insights without ledger mutation privileges
Full article198 words · extracted from arxiv.org · click to collapse
Digital payment infrastructures increasingly provide adolescent users with direct access to real-time financial services. While early access promotes financial literacy and digital inclusion, it exposes young users to severe risks of impulsive spending, social engineering frauds, unauthorized transactions, and merchant exploitation. Conventional countermeasures rely on probabilistic machine learning or rigid static controls. However, allowing probabilistic or generative artificial intelligence (AI) models to directly influence real-time payment authorization introduces non-determinism, unpredictable edge-case behavior, and critical audit vulnerabilities. This paper introduces Financial Safety for Teens Pay (FST Pay) as an architectural and formal specification. FST Pay is founded on an immutable operational boundary: strict deterministic safety gating on the real-time authorization path coupled with decoupled downstream AI explanation. Transactions initiated via rails like UPI are subjected to six deterministic invariant checks covering spending limits, guardian co-sign policies, transaction amount thresholds, merchant category codes, temporal access intervals, and hardware integrity constraints. Transactions are classified strictly into ALLOW, REVIEW, or BLOCK outcomes through an ordered, mutually exclusive decision function. High-risk transactions trigger an asynchronous guardian co-sign workflow. Generative AI is relegated entirely downstream of settlement, consuming published post-decision events solely to generate natural-language financial insights without holding mutation privileges over the ledger.
Text extracted automatically; images, tables and formatting may be missing. Original: https://arxiv.org/abs/2609.11195