diff --git a/crates/ui-egui/src/icons.rs b/crates/ui-egui/src/icons.rs
index 52476db6f..8987cc64c 100644
--- a/crates/ui-egui/src/icons.rs
+++ b/crates/ui-egui/src/icons.rs
@@ -187,6 +187,31 @@ mod tests {
         assert!(appearance.contains("<circle") && !pathfinder.contains("<circle"), "appearance should read as a list, not overlapping squares");
     }
 
+    // Regression test for #479: the Add and Delete Anchor Point tools' icons were drawn apart from
+    // the Pen tool's, so the three tools didn't read as one family. They are the Pen's pen with a
+    // plus or a minus beside it.
+    #[test]
+    fn the_add_and_delete_anchor_tool_icons_are_the_pen_icon_with_a_badge() {
+        let svg = |tool: &str| {
+            let name = tool_icon(tool);
+            let (_, bytes) =
+                crate::icon_data::ICONS.iter().find(|(n, _)| *n == name).unwrap_or_else(|| panic!("{tool} maps to {name}, which isn't an icon"));
+            String::from_utf8_lossy(bytes).into_owned()
+        };
+        let shapes =
+            |svg: &str| svg.lines().map(|l| l.trim().to_string()).filter(|l| l.starts_with("<path") || l.starts_with("<circle")).collect::<Vec<_>>();
+        let pen = shapes(&svg("tool-pen"));
+        assert!(!pen.is_empty(), "the Pen's icon has shapes");
+        let (add, delete) = (shapes(&svg("tool-pen-add")), shapes(&svg("tool-pen-delete")));
+        for (tool, icon) in [("tool-pen-add", &add), ("tool-pen-delete", &delete)] {
+            for shape in &pen {
+                assert!(icon.contains(shape), "{tool}'s icon lacks the Pen's {shape}");
+            }
+            assert!(icon.len() > pen.len(), "{tool}'s icon has a badge of its own");
+        }
+        assert_ne!(add, delete, "plus and minus differ");
+    }
+
     #[test]
     fn shared_catalog_preserves_fallback_and_tool_aliases() {
         let ImageSource::Bytes { uri, bytes } = source("missing-icon") else { panic!("expected SVG bytes") };