If I entered the syntax as field value, it can be processed by server. I would like to know how we can provide a list of tokens for users to choose from instead of asking them to type in the syntax manually as they may not know it.

This page lists all of the ones I know.  I don't think there is an API call to get a list of the tokens, and it doesn't really make sense to have one, since your application would typically show a meaningful text label to the user instead of the token itself.  But to do that, you need to know in advance what the complete list is.

I'm looking for an API that returns a list of 'meaningful text label' along with the syntax. The text label will be displayed to users and the syntax will be applied underneath when uploading to the server. When you say 'know in advance', do you mean that we need to hard code the list somewhere in the application since we cannot retrieve it programmatically? If that is the case, will it be possible that the list can be different from company A to company B? Since our application will be used by multiple customers, unless it's always the same and cannot be modified by customers, the hard-code way doesn't seem to be a good solution. Do you have other suggestions how to solve the problem?

The linked list is an unofficial document for LF 8.0. Do you have an equivalent one for 9.0 with same info, or they're exactly the same?

Thanks for the info. Although it doesn't specify clearly the convertible data type for each one, I should be able to figure it out based on the description. Given that this is a static list with no customer update allowed, I will save the list somewhere in the application with name, symbol and supported data type included, and present it for user selection from UI.  Hopefully this will achieve the same feature as what LF client provides.

Thank you all for your support.