Preventing 'Add Field' in Multivalue Parameter for tool used in ModelBuilder

Question

I made a Field Picker script to allow the user to select field names which are then used in another script for more processing with update and insert cursors.

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Is it possible to prevent them from adding their own field with the Add Field button?

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If this button cannot be removed, is there a better way to get user input where they can select Field names and I can pass those as strings to another script?

Answer 1

As commented by @Hornbydd:

You cannot remove that button. Just accept it is there and provide decent parameter help through it's item description to guide the user.