Writer describing street cafe (6)
I believe the answer is:
bistro
'cafe' is the definition.
(I've seen this before)
'writer describing street' is the wordplay.
'writer' becomes 'biro' (I've seen this before**).
'describing' indicates putting letters inside (describe can mean to form the outline of).
'street' becomes 'st'.
'biro' placed around 'st' is 'BISTRO'.
(Other definitions for bistro that I've seen before include "Modest restaurant" , "Small bar-cum-restaurant" , "Small inexpensive eatery" , "A small informal restaurant from France" , "family concern perhaps" .)