Inspector Wants "Specifications For The Mag-Lock System", What Would That Be?

It means he does not have a clue.

Typically they want spec sheets (for everything) and wiring diagrams - how you intend to build it - all of the parts and pieces. If there is a smoke detector required (depends on the jurisdiction) include that too. Don't forget (since you wrote mag-lock) to include the power supply and fire alarm interrupt. Usually that is installed by the fire alarm service company.

He is likely asking for details on the access control system. You may ask him to clarify his question, and make it clear to him whether or not you're even using maglocks.

Remember, the AHJ may be a clown, but they deserve respect and have a thankless job. See: AHJ / Authority Having Jurisdiction Tutorial

Not to promote any specific manufacturer, but Securitron (part of Assa Abloy) published a document called Code Inspectors Handbook for understanding Electric Locking Hardware a few years back.

I don't know if this has been updated to reflect current codes, but always thought it did a good job of addressing this topic in detail.

Before anything else, I think that Undisclosed 1 needs to tell us what his scope of work is on this project.

If it actually involves any access control design or installation WITHOUT any mag-locks, that's something that needs to be addressed very carefully to avoid any appearance of incompetence. But at least he has the fallback of, "We're not using mag-locks, so that's where the confusion came from."

If, God forbid, it actually involves access control WITH mag-locks, then I would have a partner or whomever has the expertise respond at first, and after demonstrating mastery bring the OP back in.

But, if he is doing video surveillance and nothing to do with Access, then he should go at once to the AHJ and state so. The longer he waits in this case, the worse the impression, and even after it gets clarified, the AHJ may still have some lingering doubts about why the OP didn't just say, "That's not me" right away.

I think the AHJ has shown some remarkable insight on the issue (assuming he knows what he is talking about). I have seen many installations of mag locks that have not met Code. It is all about the DESIGN of the "system" to include all the components that control the lock. Fire rating of the door also need to be considered. If I were you, I would first review the applicable code (under "Means of Egress: Access Controlled Doors), a drawing of how you intend to wire the lock and all the connections involved; but know that even if you do submit all this, and its approved, and if it's wrong, you are still responsible.