ok I just had a case where one civilization outrun me at building a galactic achievement/trade good
and I had espionage : HIGH with this civilization

I think that as I should have been able to see the planet building it manually (by clicking on every planet)
spies should report that kind of important information directly to me
for example :
-we just spotted this race building this trade good and that it is expected to be finished in x weeks
or
-as we know that you are building this trade good, please take note that we know of reliable source that this race is also building it & are expected to finish it before/after you

if this kind of information is not delivered directly to the player, well spies are useless
because I can't review every planet they have each couple of turns, that's a too gigantic task

thanks for reading this.