Three composable tools for the full remittance stack: mandatory CFPB Reg E subpart B disclosure arithmetic, World Bank RPW corridor cost benchmarking against the SDG 10.c 3% target, and stablecoin corridor all-in economics (Felix/Circle USDC case study). Run them standalone or chain them for end-to-end compliance plus cost analysis.
Sending money across borders costs too much. The World Bank Remittance Prices Worldwide (RPW) database tracks average total costs per corridor every quarter. The Q1 2026 global SmaRT average sits at 6.36% of the send amount. The UN Sustainable Development Goal 10.c (SDG 10.c) calls for reducing costs to 3% or below by 2030. Most corridors are still 2x above that target.
The cost comes from two sources: the provider fee (flat or percentage) and the FX markup (the spread between the rate applied and the interbank mid-market rate). Transparency of both is the core of CFPB Reg E subpart B, which requires senders to receive a written disclosure of the transfer amount, exchange rate, fees, taxes, and the amount that will be received before each transfer.
FX markup alone accounts for roughly 35% of traditional MTO corridor cost, yet it is invisible to consumers who only see the displayed rate. The World Bank RPW methodology captures it explicitly: total_cost_pct = fee_pct + fx_margin_pct, where fx_margin_pct = (mid_rate - applied_rate) / mid_rate. This is the field set replicated in compare_corridor_cost.
Felix is the send-to-Mexico product built on Circle USDC and the Stellar network, with Bitso handling Mexican peso off-ramp and SPEI local rail delivery. It demonstrates how a stablecoin corridor can achieve costs well below both the RPW corridor average and the SDG 3% target at typical consumer send amounts.
At $1,000 send amount with a $2.99 flat fee and a competitive FX rate (17.15 vs mid 17.21), the total cost works out to approximately 0.65% -- well under the RPW $500 corridor average of 2.99% and the SDG 3% target.
The stablecoin rail compresses cost in two ways. First, near-zero chain fees on Stellar (fractions of a cent per transaction) replace correspondent pre-funding cost. Second, Bitso's direct liquidity access means the FX spread is tighter than a traditional MTO's banked spread. The model_stablecoin_corridor_economics tool lets you parameterise all four cost components and compute the exact break-even send amount where stablecoin rails become cheaper than a traditional MTO benchmark.
Break-even occurs where the fixed chain fee per transaction is outweighed by the variable cost savings vs traditional MTO. Formula: break_even = chain_fee_usd * 100 / (mto_cost_pct - stablecoin_variable_pct). With Stellar fees near $0.01 and a 6% MTO baseline, break-even occurs around $1.00 -- meaning stablecoin rails are cheaper for virtually all consumer send amounts.
Any person who provides remittance transfers in the normal course of business is a remittance transfer provider under CFPB Reg E subpart B (12 CFR 1005.30 et seq.). Before each transfer is made, the provider must give the sender a written disclosure containing specific fields.
| Disclosure Field | Reg E Citation | Tool Output Field |
|---|---|---|
| Transfer amount (in USD) | 12 CFR 1005.31(b)(1)(i) | transfer_amount_usd |
| Exchange rate | 12 CFR 1005.31(b)(1)(ii) | exchange_rate_disclosed |
| Fees charged by provider | 12 CFR 1005.31(b)(1)(iii) | provider_fee, third_party_fees |
| Any taxes collected | 12 CFR 1005.31(b)(1)(iv) | taxes |
| Total amount to sender | 12 CFR 1005.31(b)(1)(v) | total_to_sender_usd |
| Amount to be received | 12 CFR 1005.31(b)(2) | amount_received_dest |
| Accounting identity check | ยง1005.31(b) internal consistency | accounting_identity_ok |
The estimate_permissible flag governs which statutory path applies. Under 12 CFR 1005.32, a provider may use estimates if it cannot determine the exact exchange rate at the time of disclosure (e.g., certain banking institution exemptions or situations where the exchange rate fluctuates). When estimate_permissible=true, disclosure_type is set to ESTIMATED. The gated chain remittance-disclosure-and-corridor-cost gates on this flag: if true, the chain exits after the disclosure step with the ESTIMATED receipt. If false (the default exact-disclosure path), it proceeds to corridor cost benchmarking.
The anchor_surface field in compute_remittance_disclosure output points to https://anchor.ainumbers.co/mcp. This enables a pre-transfer tamper-evident receipt: the disclosure artifact can be timestamped immediately after computation, creating a verifiable record for 12 CFR 1005.33 error-resolution purposes without storing any PII.
Three OCG nodes cover the remittance and FX-corridor space. Each is standalone via MCP or browser, and they compose naturally via the two chains below.
Two OpenChainGraph chains compose the tools above into end-to-end workflows.
Reg E Subpart B (12 CFR 1005.30 through 1005.36) was finalized by the CFPB in 2012 and applies to remittance transfers sent from the United States to foreign countries. It requires pre-transfer and receipt disclosures, error resolution within defined timelines (12 CFR 1005.33), and cancellation rights within 30 minutes. The estimate_permissible flag (12 CFR 1005.32) allows providers in certain categories to disclose estimated exchange rates under specific conditions; the exact vs estimated distinction matters for error-resolution liability.
SDG 10.c is part of the UN 2030 Agenda for Sustainable Development (Goal 10: Reduce Inequality Within and Among Countries). Target 10.c reads: "By 2030, reduce to less than 3 per cent the transaction costs of migrant remittances and eliminate remittance corridors with costs higher than 5 per cent." The World Bank RPW database is the primary tracking mechanism. As of Q1 2026, the global SmaRT average remains at 6.36%, and no major corridor has reached the 3% target through traditional MTO rails alone.
World Bank SmaRT Methodology measures total cost as the sum of fee % (provider fee as a percentage of the send amount) and FX margin % (the spread between the mid-market rate and the applied rate, as a percentage of the mid-market rate). The RPW database samples multiple service providers per corridor at $200 and $500 send amounts each quarter. compare_corridor_cost replicates this computation exactly.
compare_corridor_cost uses World Bank RPW cross-corridor benchmarking (fee % + FX margin %). For protocol-specific economics, use: model_x402_settlement (x402 protocol), model_tempo_payment_economics (Tempo Network), model_arc_cpn_economics (Arc Protocol CPN). For Reg E disclosure arithmetic, use compute_remittance_disclosure.