MANDATESHIELD FOR MARKETPLACES
Policy enforcement for multi-merchant agent checkout
Normalize seller and checkout evidence across a marketplace, then reserve and consume the customer's authority consistently before submission.
Current support boundary
This page describes an architecture pattern, not evidence of a customer deployment or provider adoption. Terminal outcome checking currently covers configured Stripe PaymentIntents and the supported x402 EIP-3009 profile only. Production requires provider credentials to be absent from the agent and alternate provider egress to be blocked. If native controls already satisfy the complete requirement, an additional MandateShield boundary may be unnecessary.
Who this is for
Marketplaces, booking platforms and aggregators where an agent can compare, select and buy from multiple sellers.
The execution risk
Search and ranking steps can change sellers, fees and availability between approval and payment. Marketplace complexity makes merchant binding and final-total validation essential.
How the control fits
- Represent the selected seller with a stable marketplace merchant ID.
- Include fees, taxes and shipping in the final amount.
- Verify signed purchase facts against the immutable registered customer mandate.
- Reserve cumulative headroom, require provider-bound CONSUME and one fresh redemption before submission, then reconcile the exact attempt without retrying ambiguity.
Controls included
The operational result
For an architecture that forces its supported payment path through the Gate, one account policy can mediate multiple sellers without embedding model-specific logic in every checkout.
Check a purchase boundary now
Use the public validator with sample data, or integrate strict reservation plus processor-side CONSUME before provider submission.
Open free validator →