I agree with Breno.
Serializing the JSON object into a string can be a good workaround when the object is not being passed as expected between the flow and the Common Module or Bot Flow.
The main point I would reinforce is the string size limit. Architect string variables have a limit of 32,000 characters, so this approach is safer for small or controlled payloads. If the JSON can grow over time, especially with customer data, arrays, history, or nested objects, it is important to validate the payload size before relying on this solution.
For larger payloads, I would avoid passing the full JSON through the flow. In that case, passing only the required fields, or passing a correlation ID and retrieving the full payload from an external system or Data Action, would be a cleaner and safer approach.
So, the string approach can work, but I would treat the 32K limit as an important design constraint.
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Arthur Pereira Reinoldes
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