ProgID

ProgIDs are the human-readable equivalent of Microsoft COM CLSID values. There is a Win32 API to convert from one to the other (ProgIDFromCLSID). ProgIDs are what you pass to scripting applications to create COM objects.

Is this the "application name" tcom needs? Yes.

Example values:

InternetExplorer.Application

 package require tcom
 set ie [tcom::ref createobject "InternetExplorer.Application"]
 $ie Visible 1
 $ie Navigate https://www.tcl-lang.org/

See also "registry".