Добавьте файлы проекта.

YandexMusic.API/Models/Search/Artist/YSearchArtist.cs

@@ -0,0 +1,15 @@
+using YandexMusic.API.Models.Common.Cover;
+
+namespace YandexMusic.API.Models.Search.Artist
+{
+    public class YSearchArtist
+    {
+        public bool Composer { get; set; }
+        [JsonConverter(typeof(YCoverConverter))]
+        public YCover Cover { get; set; }
+        public List<string> Decomposed { get; set; }
+        public string Id { get; set; }
+        public string Name { get; set; }
+        public bool Various { get; set; }
+    }
+}

YandexMusic.API/Models/Search/Artist/YSearchArtistCounter.cs

@@ -0,0 +1,10 @@
+namespace YandexMusic.API.Models.Search.Artist
+{
+    public class YSearchArtistCounter
+    {
+        public int? AlsoAlbums { get; set; }
+        public int? AlsoTracks { get; set; }
+        public int? DirectAlbums { get; set; }
+        public int? Tracks { get; set; }
+    }
+}

YandexMusic.API/Models/Search/Artist/YSearchArtistModel.cs

@@ -0,0 +1,11 @@
+using YandexMusic.API.Models.Artist;
+using YandexMusic.API.Models.Search.Track;
+
+namespace YandexMusic.API.Models.Search.Artist
+{
+    public class YSearchArtistModel : YArtist
+    {
+        public List<YSearchTrackModel> PopularTracks { get; set; }
+        public List<string> Regions { get; set; }
+    }
+}