FlexCard performance is directly influenced by the amount of data transferred between the server and the client. Returning only the fields required for display, calculations, or actions minimizes payload size, improves rendering speed, reduces network traffic, and simplifies maintenance. Returning every available field may seem flexible, but it increases response size and can negatively affect performance, particularly on mobile devices and slower networks. Concatenating fields into a single value reduces usability and limits downstream processing options. XML standardization is unrelated to FlexCard optimization. Salesforce recommends trimming data returned from Integration Procedures and Data Mappers so that only necessary information is passed to consuming components. This principle is a core OmniStudio performance best practice and contributes to faster, more scalable user experiences.

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