Hi @Santiago Montoya,
Question: Who or What need to retrieve the image? the agent? Architect, when the interaction start and is process by message? An external process?
If you use the execution data history for your flow, when the interaction start, in the flow you will see a variable "Message.Message", where you could see the uri of attachment. In theory, having the uri and permisions, you could retrieve the image. I have not tested yet myself, I have a similar request but I have been busy.

Regards,
SG
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Saugort Dario Garcia
Arquitecto de soluciones
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