Blue Circles within my city

[Mklangelo]

Is this a recommendation to build a cottage here?

 

[Kerran]

Not necessarily a cottage, but it does mean the AI thinks your worker should improve one of the blue-ringed tiles first. You will also notice blue borders around some of the action icons; these are the improvements the AI suggests.

 

[JonathanStrange]

Sometimes they're even good suggestions, mostly though you'd have done them anyways!