Wiktionary
pavement artist
n. 1 An artist who draws pictures on the pavement, often hoping to get donations from the passers-by. 2 (context espionage English) A specialist in outdoor surveillance as a pedestrian.
WordNet
pavement artist
n. someone who draws on the pavement with colored chalks (hoping that passers-by will give them money)
Usage examples of "pavement artist".
We couldn't have him picking some half-arsed little pavement artist: it had to be a big gun to make the story stick.
Her real taste was illustrated in that water-colour by the pavement artist, the one she had paid half-a-crown for (and thirty-five shillings for the frame).