If you need to open any type of record but don’t know the URL. No worries just specify object type code (you can get object type code from CRM SDK under section” Entity Type Codes”) and ID it will open your record. (Note that the parameter names are case sensitive here)
To open a record in ReadOnly mode
You can call these from anywhere in CRM and it will identify the entity and open the relevant entity form. This does away the need or specifying url specific to the entity.