Register at the Mastercard Developers portal and provision sandbox credentials for the Open Banking US (Finicity) lending product group
Create a customer record via POST /aggregation/v2/customers/active (or testing variant in sandbox) and capture the returned customerId
Generate a Connect URL for the consumer via the Finicity Connect flow; the consumer links their bank accounts through the hosted UI
Once accounts are linked, initiate a VOA report via POST /decisioning/v2/customers/{customerId}/voa; receive a reportId in the response
Poll GET /decisioning/v2/customers/{customerId}/reports/{reportId} or listen for the report completion event to retrieve the finished VOA report
Parse the report for account balances, 12-month average balance, and cash-flow data; for GSE submission, use the audit copy or the report token for Fannie Mae / Freddie Mac integration
Known gotchas
The VOA report automatically sends 12 months of data to Fannie Mae when submitted via the GSE channel — ensure your integration does not truncate the history if the lender requires full GSE compliance
Finicity APIs are now published under both the legacy finicity.com developer portal and the new Mastercard Developers portal; use the Mastercard Developers portal (developer.mastercard.com/open-finance-us) for current endpoint documentation
Consumer re-permissioning may be required after a Connect session expires; implement token refresh or a new Connect session trigger in your workflow
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp