Gap between retaining wall and pathway

[Salam123]

Need expert opinion for pathways 

I hate weeds and bits growing on the edges of pathway . I have asked builder to have zero gap between retaining wall and pathway 

He came back with following question

” Best we can do is to keep concrete 35mm away from shark fin post bracket as you need clearance for fence posts and rails as the concrete path will be higher than retaining wall. Are you happy to keep the concrete path 35 mm off the post bracket”

what is your expert opinion. Please note he will not do anything with the retaining wall. It is not in his scope.