Your question is Design HTTP APIs. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Design HTTP APIs in a system design round.
Keep the scope to request/response APIs for a Visa risk-scoring service. Focus on API shape, versioning, auth, idempotency, latency, and error handling, and be explicit about what the client sends versus what the service enriches internally.