Santa Clara LAFCO is authoritative for the boundaries of cities within Santa Clara County. It is not the authority on addresses within the cities, or roads, or anything else.

The import was from an authoritative data source, the City of San José. You can browse the data here: https://csj.maps.arcgis.com/apps/webappviewer/index.html?id=3c5516412b594e79bd25c49f10fc672f

Anything that physically exists is valid to map, even if it's illegal or dangerous to traverse. In these cases they should be tagged with the "access" or "hazard" keys as appropriate. Otherwise someone will just add them back later.

You can see the history of an object by following its link and clicking "view history." In this case way/810015282/history we can see that it was from an import changeset/85987477 I also notice that the building had an address on it, which seems like valuable information to keep somewhere.

Please use descriptive changeset descriptions: osm.wiki/Good_changeset_comments The "name" field should be for the name of an object, not the route number: osm.wiki/Names I've reverted this change in changeset/138682086

If an object was previously known by another name, it's helpful to put that in "old_name=*" so that people searching for the old name can still find it.

When improving the geometry of a feature, it's better to add and realign the existing feature than to delete and re-draw. See osm.wiki/Keep_the_history . You can add nodes to an existing way by dragging the arrow between two nodes.

access=no doesn't mean nobody at all can ever use it—otherwise, it wouldn't exist. It means it can't be generally used, but that can still allow for e.g. emergencies or maintenance workers.

If the stairs are accessible from the freeway, they need to connect to the freeway in OSM too, even if it means an awkward crossing to the centerline. This ensures a proper routing network.

When objects close down, it's often better to re-tag them with a lifecycle prefix osm.wiki/Lifecycle_prefix than to delete them entirely. This way, any potential future features can re-use the old data, for example geometry or address/phone tags.

Anything that physically exists is allowed to be mapped, even if you're not allowed to use it. In these cases, consider access=no. I know it seems silly to try and maintain a routing network of inaccessible paths, but I could imagine for example an app that would find the nearest freeway refuge in emergencies.

Nice!

You can map traffic signs, including speed limits: traffic_sign=* and I don't think it's redundant to do so: the sign is a physical object that can be mapped, and the limit is an attribute of the road or rail.

Do I understand right, that the fixme asked how to tag something, and because there is no tag for it currently, you simply removed the fixme? If a tag for it is made in the future, that will make this hard to find.

In the absence of separate sidewalk ways, however, it is necessary to connect them to maintain the pedestrian routing network.

Many of these businesses that you've added were already mapped as part of the buildings. Please check that you don't add duplicate data.

Just because it isn't typical doesn't mean it's wrong.

It is tagged surface=dirt, and it should not be tagged natural=sand. Neither should SF Giants stadium.

"This tag should not be used for the infields of baseball or softball fields (a form of tagging for the renderer) - use surface=dirt instead." - natural=sand

Thanks. I changed the outer part to a building outline and filled in the rest of the building parts: changeset/137765483