Secret Angent had an original box art.

Okay, so it might not be a box art per se but much better than what we have now who doesn't even slightly resembles the game. First I came to think of was James Bond but when I saw the screenshots I remember I played this hundred years ago.

I did wonder about the choice of box art but as I only ever played the shareware version I never actually got to see an original boxed copy of secret agent.

Or was it really just like the title screen of the game?

Is there actually box art/a boxed copy? I can't find any evidence of an actual boxed copy online.

Also, what's wrong with artwork that seeks to be reminiscent of James Bond; after all, the game is decidedly inspired by James Bond - here are the first words on the page you linked:

"You're agent 006"

Anyway, the way that GOGs product pages work is that they require a tall image to be used as boxart, if there isn't one, then they need to create one. Personally, I really like the artwork they created for it; although, I do agree that maybe it could have had more relevance to the game itself (maybe some kind of blueprint motif?)

Apogee never commissioned box art for this game so the 3dr page uses the title screen. this game was too early to even get ad art made for it. Cosmo has art but was never sold by formgen in an box.

That's a bit disappointing that there never was a box. The gog choice is ok but I guess I would prefer if it was a little more obviously inspired by the title screen but we cant have everything.