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# External Functions

Functions in  applications are strictly external, meaning they can only be invoked through trans- actions from outside the application or by the orchestration layer. Direct function calls from one function to another within the same application are not supported. This design ensures:

* Clear separation of entry points, simplifying execution flow.
* Modular interaction with the application, as each function operates independently.  
* Improved transparency and security by explicitly restricting internal function calls.