When setting up a function it is possible to prompt M3 for legal values of i.e. item groups.

To prompt for a value, click on the "..." button next to the input field.

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A new window will open displaying the possible values. Select a value and click "Ok"

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To set this up, create or edit a function with the configurator. On the input field, click the "Add lookup API" button.

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Select an M3 program, transaction and which fields to use. Also mark the default field, which will be sent to the input field. Save.

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Finish editing the function and save it. The prompt will be available for use.