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Overview

Exceptions or errors that occur when a Generative Function is being run by the app cause that evaluation of the Generative Function to fail. Any Experiment that’s running in the app will continue, but no output results will be available for the failed evaluation.

Check in the terminal where you’ve started the Function Server for further logging of the exceptions that occur, and if that doesn’t help then contact us for further support.

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Exceptions

Exceptions can occur in functions that you call (either built-in Python functions or ones from external libraries). It’s good practice to handle these errors, either allowing the Generative Function to continue, or throwing another error with a clear message about what’s gone wrong.

If an instance of a Generative Type is created incorrectly, for example if a value for a field is missed or is out of the allowed range set by the [Field limits]((/guides/python/concepts/generative-types#field), then a validation error will be raised - see Pydantic’s docs for further information.