A recid is the primary unique identifier for any record in INSPIRE. It is the string of numbers at the end of a url for the detailed view of a record.
You can use it to search for a specific record, using the search terms fin recid and the recid.
You can also use it to search for a record in bibedit by entering it in the box in the upper left of the screen and clicking ‘Search’. The 001 field of a record will contain its recid. This field cannot be edited.