Tagging narrow roads

In the city I’m living in, there are so many narrow public roads that only one motorcar can pass through them in one line at the same time. Although it’s not legally forbidden but These type of roads aren’t suitable for thru-traffic and it is advisable for motorcars to use them only if the destination is located in them. How should i tag roads of this sort? Thanks in advance

highway=residential or highway=unclassified (depending whether there’s apartments close to the road) means it’s not suitable for thru-traffic.

If there’s a legally restricted maximum width (with appropriate signal) use maxwidth=…

Hi, the access tag might suit this situation, it could be access=destination or access=discouraged. Please see here:- https://wiki.openstreetmap.org/wiki/Key:access
You can only have one access tag on a way so the allowed/discouraged traffic should be independently tagged.

highway=service, service=alley would be another possibility - see https://wiki.openstreetmap.org/wiki/Tag:service=alley

https://wiki.openstreetmap.org/wiki/Key:lanes might be useful, as might a “width” tag. I can think of at least one renderer that processes those when deciding how to render roads.

Thank you all who have replied to my question so quickly.