Flight Attendant reported being notified during taxi by a passenger that his gate checked bag contained his Laptop. Captain was notified and flight returned to gate to retrieve the Laptop.

Narrative

Operational Issue - Flight Attendants (FA) notified Agents at XA:34 bins were full and bags needed to be gate checked. No response from Agents. Would have been great if Agents proactively began checking bags of passengers who were still waiting on jetbridge; but this didn't happen. I advised all passengers via PA to go to the front of the aircraft to speak with the Agent about checking bags; as per manual; Agent and passenger need to have conversation regarding batteries; e-cigarettes; etc. This was not happening! Agents were simply taking the bags to be checked and tagging them with a generic tag; no seat number and no last name! This is not only a security issue; but ruins the customer experience as now the customer has no means of recourse if bag is lost because no passengers received a bag tag! We departed 5 minutes late because of this and pushed back from gate. Passengers then notified FAs that he had a laptop in his gate checked bag. I notified the Captain as per manual. We returned to gate; had ground crew pull bag; and passengers removed his laptop resulting in a departure of XB:09; 24 minute delay. Had Agents checked bags proactively and completed conversation re: batteries with each passenger; this could have all been avoided.Suggestions - Please remind everyone to follow policies and procedures; even when under pressure. Procedure for Agent to have conversation with each passenger for gate checked bags did not happen resulting in us having to return to the gate and delay the flight even further. Additionally; manual is confusing. It would be great if this could include a diagram or reference to items containing lithium ion batteries like laptop; cell phone; tablet; etc.; and indicate if these are allowed to be in checked bags or not. Upon further investigation during the flight; the Pilots informed me that per their FOM it was actually ok if that passenger's checked bag contained a laptop as the lithium ion battery was attached to the laptop and not separate. However; in the heat of the moment; that was not clear in either the FAs manual or the Pilots FOM. We could have avoided that entire situation. Please consider reformatting this section to make it more clear for both FAs and Pilots.