Workflow states
Model pending, submitted, review, approved, rejected and retry states explicitly. Do not reduce complex provider responses to an ambiguous boolean.
Provider boundary
Keep provider-specific API logic behind an integration service so onboarding applications are not tightly coupled to one vendor.
Retries and webhooks
Design idempotent callbacks, retry handling and reconciliation for delayed or duplicated provider events.
Manual review
Route exceptions to authorized operations with documented reason codes and audit history.
Data minimization
Collect and retain only the information needed for the broker’s legitimate and applicable process, with appropriate security and retention policies.
User experience
Explain status and required next steps without exposing sensitive internal rules or provider credentials.
Monitoring
Alert on callback failures, unusual queue growth and reconciliation exceptions.