KeepRight is a data consistance and quality assurance tool for OSM. It’s been around for years and years (since at least 2009). I used it ages ago and forgot about it. But it’s still around, still updating, still checking OSM. Some of the checks don’t make sense everywhere, so use your head and mark things as false positives if needed. If you’re looking for some mapping & gardening, open it up, have a look at an area and fix up the map.