Author: lonvia
[Added to the original trac issue at 12.03pm, Wednesday, 13th January 2016]

You cannot restrict a reverse query by osm_type.

If you are trying to restrict reverse resilts to street level then try: http://nominatim.openstreetmap.org/reverse?format=json&lat=31.515380035347903&lon=-9.77214052951257&addressdetails=1&zoom=17

Author: capellsk
[Added to the original trac issue at 2.44am, Thursday, 14th January 2016]

Okay, as soon as wiki account creation gets fixed (it's broken) I will remove the line where it says you can use osm_type with reverse.

Your comment, lonvia, about the zoom level indicates that perhaps the zoom levels have semantic meaning in addition to scale (ie, zoom of 18 will produce a "building" and 17 a "street"). The OSM wiki page mostly talks about scale, with a little semantics mixed in:

http://wiki.openstreetmap.org/wiki/Zoom_levels

Here is what I get using that same query with different zooms:
18+ - restaurant (node)
17 - footway (way)
16 - same
15 - suburb (node)
14 - same
13 - same
12 - same
11 - city (relation)
10 - same
9 - county (relation)
8 - same
7 - state_district (relation)
6 - same
5 - state (relation)
4 - country (relation)
3 - same
2 - same
1 - same
0 - same

Oddly, OSM has 0-19 and Nominatim has 0-18 (according to the wiki).

So does Nominatim (or OSM) use the zoom levels in a semantically consistent way? For example, will zoom 10 or 11 always give the city, or could a city show up at any zoom level depending on its size?

Author: capellsk
[Added to the original trac issue at 4.03am, Thursday, 14th January 2016]

I updated the wiki page to reflect the fact that osm_type is not supported by reverse.

Author: TomH
[Added to the original trac issue at 7.11am, Thursday, 14th January 2016]

I've reverted that edit, as you misunderstood.

You either use lat+lon or osm_type+osm_id to do a reverse geocode. What you can't do is combine them to do the geocode by lat+lon and also filter by type.