Mostly making types more specific. Within a service, ensuring semantics are part of the type so they can be checked statically, and designing function boundarie

Mostly making types more specific. Within a service, ensuring semantics are part of the type so they can be checked statically, and designing function boundaries so those semantics are part of the interface. Between services, using standardized machine-usable docs (like OpenAPI and JSONSchema) to share those types in a well-defined way. This is harder because network boundaries are less flexible, but it does help a lot.