But for locking a topic there's nothing to signify it was a moderator action.
I just think it would be a nice courtesy if mods would just add a post before locking a topic to justify why they felt it should be locked. It's good to put this info on the record for future reference.
There isn’t any complication on who can luck a post or not. It’s always going to be either a moderator or the OP as, no forum user can just take actions on a post that wasn’t originally created by them.
Meanwhile, a moderator note wouldn’t be so bad. As this wouldn’t only serve for the OP alone but, would in a way relate to the rest of the forum users some specifics. Mind you, only the OP would be of full knowledge on whom might have locked a thread as, if it ain’t OP’s actions, it’s definitely going to be a moderator but, the rest of the forum members can’t know that. A moderators note could however, spill this secrete as to reasons why, it would serve as a reference point and by some means, serve as a deterrent for those who would like to create similar post.
This however might be a lot of work for moderators and could be ignored since it doesn’t matter much but, it’s a thought still.