Prompt

Design inter-service communication patterns.

<services>
{list services and their responsibilities}
</services>

<communication_needs>
{sync/async requirements, data flow}
</communication_needs>

<constraints>
{latency, reliability, scalability needs}
</constraints>

Design:
1. Sync vs async decisions
2. Protocol selection (REST/gRPC/events)
3. Service discovery approach
4. Circuit breaker patterns
5. Distributed tracing setup
6. API gateway strategy