Calling Custom APIs from Smartsheet form

edited 12/09/19 in API & Developers

Hi All,  we have a simply custom API which will take as input an employees ID and return their management chain.  We would like to call this API as part of a simple smartsheet form we built such that their supervisor's ID can be inserted as part of the record in the smartsheet.  Are there instructions as to how to embed a custom API into a smartsheet form?