Strings are recognized and annotated, or labeled, with a type label by a recognizer plug-in. Application program modules may use the type label and other metadata to provide users with a choice of electronic commerce actions. In addition, the user may be provided with a download Uniform Resource Locator (URL) and download action plug-ins for that type label. An ActionGUID may be used to specify the class ids (CLSIDs) of the action plug-ins that may provide actions for a particular semantic category type label. Each DLL has a class id (CLSID), which is a GUID. The ActionGUID is a GUID that is specified by the recognizer plug-in and which corresponds to the CLSID(s) of the only action plug-ins that should be permitted to provide actions for the semantic category type label provided by the recognizer plug-in.