Fix issue #4303: Check output type if it is a string before performing .toLowerCase()

[hanna-daoud]

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Summary

Fixes issue #4303: This PR adds a type check for output before calling .toLowerCase() to ensure it is a string. This prevents potential runtime errors when output is undefined or not a string.

Change Type

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• Bug fix (non-breaking change which fixes an issue)

Testing

Create an assistant action, and let the assistant call it. It used to throw errors and break the UI, now it works perfectly.

Test Configuration:

Checklist

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• My code adheres to this project's style guidelines
• I have performed a self-review of my own code
• My changes do not introduce new warnings

[danny-avila]

Are you sure that your custom endpoint is even being used? looking at the code, it should actually fail, and maybe another configured endpoint is being used

Or is this fix exclusively for use with Assistants, not Agents?

[hanna-daoud]

This fix is only tested on Assistants and not agents. Also, I created a fresh assistant and added only 1 endpoint for the sake of test. My endpoint is a local one so I added logging to make sure it is being accessed and yes, it is being accessed and the function is running to the end.