Permit records can help you understand what a city has on file for a property, including issued permits, statuses and inspection history where the jurisdiction makes those records available.
Building departments use their own terminology, deadlines and procedures. Treat this as a practical orientation and verify the current rule with the jurisdiction that issued — or would issue — the permit.
No. It shows what the jurisdiction has in the record you found; absence or presence of a permit does not by itself document every alteration ever made.
Look for the jurisdiction's equivalent of issued, inspection activity and final/completed status, and read the record details rather than relying only on a permit number.