Intelligent tagging uses natural language processing and other AI technologies to infer meaning from unstructured data. Apparently there is a free limited API for that called open calais by Refinitiv formerly Reuters at https://developers.refinitiv.com/open-permid/intelligent-tagging-restful-api . The API looks intimidating and an application must be made before getting a key. A preview can be seen at https://permid.org/onecalaisViewer