Data not transferred from New Call to request when request initiated from call and content of description is long if it has more than 4000 characters.
System property "glide.tiny_url_min_length" changes the url to tiny support url if the number of characters exceeds the specified value in the property.
-- By default the value of property "glide.tiny_url_min_length" is 1024 characters, so when we are trying to pass description with more than 1024 characters, the url will change as below
Decoded url: http://<instance-name>/nav_to.do?uri=/com.glideapp.servicecatalog_cat_item_view.do?sysparm_tiny=f4498c6ccccc2300964faf77e5defea3
-- So when we try to get the "sysparm_additional_information" query parameter in our client script, it will return undefined.
-- Tiny url creates an entry in the "sys_tiny_url" table, and as you can see it passes the sys_id of that record in the above URL
-- To handle this scenario you need to fire an Ajax call on "sys_tiny_url" table and fetch the record with sys_id, there you will get the value of the field that has long valu..
Here you can read more about 'Examples of navigating by URL':