For me, one important best practice is to treat Data Actions as production integrations, not just as a quick way to call an API from Architect.
I usually try to keep the request and response as simple as possible, validate only the data that Architect really needs, and avoid returning large payloads when only a few fields will be used in the flow.
Another important point is error handling. The flow should never depend on a perfect API response. I like to have clear success, failure, and timeout paths, so the customer experience does not get stuck if the external system is slow or unavailable.
I also try to avoid repeated calls when possible. If the same customer data was already retrieved once, I prefer to store it in a variable or participant data and reuse it later in the flow.
In short, good Data Actions should be simple, predictable, well-named, and designed with failure scenarios in mind.
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Raphael Poliesi
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