diff --git a/CLAUDE.md b/CLAUDE.md
index f4507e8..6519910 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -17,6 +17,8 @@ The name for the App is KOOGLE. Koogle is an app for club management.
 - Automatic or rule-based cost allocation
 - Evaluation per person/day/game
 - User-related actions (CurrentUserService)
+- cash book
+- plugin system for different game logics
 
 ### Technical
 - ASP.NET Core backend
@@ -29,7 +31,7 @@ The name for the App is KOOGLE. Koogle is an app for club management.
 - maybe in future also for darts, soccer betting pools, Leisure groups, Sport clubs, etc.
 
 **Phase 1 MVP:** See [docs/IMPLEMENTATION_PLAN.md](./docs/IMPLEMENTATION_PLAN.md)
-- 23 granular phases (A1-F3)
+- granular phases (A1-K23)
 - Foundation → Clubs → Users → Persons → Days → Dashboard
 - Track progress via checkboxes in plan
 - ~75 files total
diff --git a/src/Koogle.Application/Games/FoxHunt/FoxHuntGameLogicService.cs b/src/Koogle.Application/Games/FoxHunt/FoxHuntGameLogicService.cs
index 8c47c5d..3da9532 100644
--- a/src/Koogle.Application/Games/FoxHunt/FoxHuntGameLogicService.cs
+++ b/src/Koogle.Application/Games/FoxHunt/FoxHuntGameLogicService.cs
@@ -14,6 +14,7 @@ namespace Koogle.Application.Games.FoxHunt
     /// </summary>
     public class FoxHuntGameLogicService : IGameLogicService
     {
+        /// <inheritdoc />
         public object CreateInitialModel(Guid[] playerIds, object? setupOptions)
         {
             var options = ParseSetupOptions(setupOptions);
@@ -30,13 +31,9 @@ namespace Koogle.Application.Games.FoxHunt
                 NonFoxIndex = 0,            // Index für Nicht-Fuchs-Spieler
                 FoxTurnsRemaining = options.LeadingThrows - 1,  // -1 weil erster Wurf bereits aus PlayerOrder[FoxIndex]
                 FoxTurn = true, // ein fuchs fängt an
-
                 LeadingThrows = options.LeadingThrows,
                 PlayerStates = playerStates,
                 PlayerOrder = playerOrder,
-                //CurrentPlayerIndex = 0,
-                //FoxLeadingThrowCount = 0,
-                //CurrentFoxIndex = 0,
                 WinnerId = null,
                 IsGameOver = false,
             };
@@ -44,6 +41,7 @@ namespace Koogle.Application.Games.FoxHunt
             return model;
         }
 
+        /// <inheritdoc />
         public (object UpdatedModel, ThrowResult Result) ProcessThrow(object gameModel, AfterThrowState afterThrow)
         {
             var model = this.CastModel<FoxHuntGameModel>(gameModel);
@@ -61,9 +59,7 @@ namespace Koogle.Application.Games.FoxHunt
                 });
             }
 
-            //var actualName = GetPlayerName(playerId).Result;
             var playerStates = new Dictionary<Guid, FoxHuntPlayerState>(model.PlayerStates);
-            //var eliminatedPlayers = new List<Guid>(model.EliminatedPlayers);
             var triggers = new List<TriggerEvent>();
 
             var foxId = model.PlayerOrder[model.FoxIndex];
@@ -73,19 +69,28 @@ namespace Koogle.Application.Games.FoxHunt
             if (model.FoxTurn)
             {
                 playerStates[foxId].PinCountFox+= afterThrow.PinsKnocked;
+                if (afterThrow.IsCircle)
+                {
+                    playerStates[foxId].PinCountFox += 2;
+                }
             }
             else
             {
                 playerStates[foxId].PinCountHunters+= afterThrow.PinsKnocked;
+                if (afterThrow.IsCircle)
+                {
+                    playerStates[foxId].PinCountHunters += 2;
+                }
+
                 if (playerStates[foxId].PinCountHunters >= playerStates[foxId].PinCountFox )
                 {
                     // fox has been caught
-                    isLastHunter = true;
+                    isLastHunter = true; // will cause selection of the next fox
                     playerStates[foxId].FoxCaught = true;
 
 
                     // Calculate penalty (point difference the hunters achieved)
-                    int pointDifference = playerStates[foxId].PinCountHunters - playerStates[foxId].PinCountFox;
+                    var pointDifference = playerStates[foxId].PinCountHunters - playerStates[foxId].PinCountFox;
                     if (pointDifference > 0)
                     {
                         triggers.Add(new TriggerEvent
@@ -109,7 +114,7 @@ namespace Koogle.Application.Games.FoxHunt
             var nextPlayerId = GetNextId(model, isLastHunter);
 
             // Check GAME END
-            bool isGameOver = isLastHunter && model.FoxIndex == 0;
+            var isGameOver = isLastHunter && model.FoxIndex == 0;
 
             if (isGameOver)
             {
@@ -178,7 +183,7 @@ namespace Koogle.Application.Games.FoxHunt
                 return model.PlayerOrder[model.FoxIndex];
             }
 
-            // 1️⃣ Fuchs ist 2x hintereinander dran
+            // Fuchs ist 2x hintereinander dran
             if (model.FoxTurnsRemaining > 0)
             {
                 model.FoxTurnsRemaining--;
@@ -188,7 +193,7 @@ namespace Koogle.Application.Games.FoxHunt
 
             model.FoxTurn = !model.FoxTurn; // danach abwechselnd
 
-            // 2️⃣ Abwechselnd Nicht-Fuchs → Fuchs
+            // Abwechselnd Nicht-Fuchs → Fuchs
             if (!model.FoxTurn)
             {
                 var nextNonFoxIndex = model.GetNextIndex(model.PlayerOrder, model.NonFoxIndex);
@@ -199,56 +204,26 @@ namespace Koogle.Application.Games.FoxHunt
                 }
                 model.NonFoxIndex = nextNonFoxIndex;
                 return model.PlayerOrder[nextNonFoxIndex];
-
-                // nächsten Nicht-Fuchs suchen
-                //while (model.NonFoxIndex == model.FoxIndex)
-                //    model.NonFoxIndex++;
-
-                //if (model.NonFoxIndex < model.PlayerOrder.Length)
-                //{
-                //    Guid next = model.PlayerOrder[model.NonFoxIndex];
-                //    model.NonFoxIndex++;
-                //    //model.FoxTurn = true;
-                //    return next;
-                //}
-                //else
-                //{
-                //    // Alle Nicht-Füchse durch → neuer Fuchs
-                //    model.FoxIndex++;
-                //    model.NonFoxIndex = 0;
-                //    model.FoxTurnsRemaining = model.LeadingThrows - 1;
-                //    model.FoxTurn = true;
-                //    return GetNextId(model);
-                //}
             }
 
-            
-
-
-            // 3️⃣ Fuchs-Zug im Wechsel
-            //model.FoxTurn = false;
+            // Fuchs-Zug im Wechsel
             return foxId;
         }
 
-        private static int GetNextActivePlayerIndex(
-            Guid[] playerOrder,
-            int currentIndex,
-            Dictionary<Guid, FoxHuntPlayerState> playerStates)
-        {
-            return 0;
-        }
-        
+        /// <inheritdoc />
         public (bool IsGameOver, Guid? WinnerId) CheckGameEnd(object gameModel)
         {
             var model = this.CastModel<FoxHuntGameModel>(gameModel);
             return (model.IsGameOver, model.WinnerId);
         }
 
+        /// <inheritdoc />
         public IReadOnlyDictionary<Guid, PlayerStatsSummary> GetPlayerStats(object gameModel)
         {
             throw new NotImplementedException();
         }
 
+        /// <inheritdoc />
         public GameSetupValidationResult ValidateSetup(object? setupOptions)
         {
             if (setupOptions is null)
@@ -261,7 +236,7 @@ namespace Koogle.Application.Games.FoxHunt
 
             if (options.LeadingThrows < 2 || options.LeadingThrows > 4)
             {
-                errors.Add("Vorsprung muss zwischen 6 und 12 liegen.");
+                errors.Add("Vorsprung muss zwischen 2 und 4 liegen.");
             }
 
             //TODO: validate player-count, at lease 2 players needed
@@ -271,12 +246,14 @@ namespace Koogle.Application.Games.FoxHunt
                 : GameSetupValidationResult.Valid();
         }
 
+        /// <inheritdoc />
         public IReadOnlyList<GameActionDescriptor> GetAvailableActions(object gameModel, Guid currentPlayerId)
         {
             // FoxHunt has no custom actions
             return [];
         }
 
+        /// <inheritdoc />
         public GameActionResult ExecuteAction(object gameModel, string actionId, Guid currentPlayerId,
             IReadOnlyDictionary<string, object>? parameters = null)
         {
diff --git a/src/Koogle.Application/Games/FoxHunt/FoxHuntGameModel.cs b/src/Koogle.Application/Games/FoxHunt/FoxHuntGameModel.cs
index ef6283a..d6b114d 100644
--- a/src/Koogle.Application/Games/FoxHunt/FoxHuntGameModel.cs
+++ b/src/Koogle.Application/Games/FoxHunt/FoxHuntGameModel.cs
@@ -1,34 +1,46 @@
 namespace Koogle.Application.Games.FoxHunt
 {
     /// <summary>
-    /// Game model for Fuchsjagd-Spiel (Fox Hunt) game type.
+    /// Game model for Fox Hunt (Fuchsjagd-Spiel) game type.
     /// One Player starts as fox, and all others try to hunt him.
     /// </summary>
     public record FoxHuntGameModel : IGameModel
     {
-        
+        /// <summary>
+        /// State for each player (details if fox survived or not).
+        /// </summary>
+        public Dictionary<Guid, FoxHuntPlayerState> PlayerStates { get; init; } = new();
 
-        //public int LeadingThrows { get; set; }
-        //public int FoxLeadingThrowCount { get; set; }
-        public Dictionary<Guid, FoxHuntPlayerState> PlayerStates { get; set; }
-
-        public Guid[] PlayerOrder { get; set; }
+        /// <summary>
+        /// Fixed player order (default order at game start).
+        /// </summary>
+        public Guid[] PlayerOrder { get; set; } = [];
 
         /// <summary>
         /// count of throw the fox can start with
         /// copy from setup model
         /// </summary>
-        public int LeadingThrows { get; set; } 
+        public int LeadingThrows { get; set; }
 
-        //public int CurrentPlayerIndex { get; set; }
-        //public int CurrentFoxIndex { get; set; }
+        /// <summary>
+        /// index pointing to the current fox (Index in PlayerOrder)
+        /// </summary>
+        public int FoxIndex { get; set; }              
 
+        /// <summary>
+        /// index pointing to the current hunter (Index in PlayerOrder)
+        /// </summary>
+        public int NonFoxIndex { get; set; }            
 
-        public int FoxIndex { get; set; }              // aktueller Fuchs (Index in PlayerOrder)
-        public int NonFoxIndex { get; set; }            // Index für Nicht-Fuchs-Spieler
-        public int FoxTurnsRemaining { get; set; }      // verbleibende Fuchs-Züge
-        public bool FoxTurn { get; set; }               // true = Fuchs dran im Wechsel
+        /// <summary>
+        /// remaining leading throws a fox has left
+        /// </summary>
+        public int FoxTurnsRemaining { get; set; }      
         
+        /// <summary>
+        /// true = a throw by fox, false = a throw by a hunter
+        /// </summary>
+        public bool FoxTurn { get; set; }              
         
         /// <inheritdoc/>
         public Guid? WinnerId { get; set; }
@@ -37,12 +49,34 @@
         public bool IsGameOver { get; set; }
     }
 
+    /// <summary>
+    /// Info about the last throw for UI display.
+    /// </summary>
     public record FoxHuntPlayerState
     {
+        /// <summary>
+        /// count of pins the fox has knocked.
+        /// </summary>
         public int PinCountFox { get; set; }
+
+        /// <summary>
+        /// count of pins the hunters have knocked.
+        /// </summary>
         public int PinCountHunters { get; set; }
+
+        /// <summary>
+        /// Weather the hunters have caught the fox.
+        /// </summary>
         public bool FoxCaught { get; set; }
+
+        /// <summary>
+        /// Weather the fox survived with most point difference.
+        /// </summary>
         public bool IsWinner { get; set; }
+
+        /// <summary>
+        /// Weather the fox could escape the hunters.
+        /// </summary>
         public bool FoxEscaped { get; set; }
     }
 }
diff --git a/src/Koogle.Application/Games/GameExtensions.cs b/src/Koogle.Application/Games/GameExtensions.cs
index 0c8ad11..9106ad2 100644
--- a/src/Koogle.Application/Games/GameExtensions.cs
+++ b/src/Koogle.Application/Games/GameExtensions.cs
@@ -9,8 +9,19 @@ using System.Threading.Tasks;
 
 namespace Koogle.Application.Games
 {
+    /// <summary>
+    /// Helper class for GameLogicServices
+    /// </summary>
     public static class GameLogicServiceExtension
     {
+        /// <summary>
+        /// casts an object to game model type
+        /// </summary>
+        /// <typeparam name="T">Type of the game model</typeparam>
+        /// <param name="logicService"></param>
+        /// <param name="gameModel"></param>
+        /// <returns></returns>
+        /// <exception cref="InvalidOperationException"></exception>
         public static T CastModel<T>(this IGameLogicService logicService, object gameModel) where T : IGameModel
         {
             if (gameModel is T model)
@@ -29,8 +40,18 @@ namespace Koogle.Application.Games
         }
     }
 
+    /// <summary>
+    /// Helper methods for GameModel
+    /// </summary>
     public static class GameModelExtensions
     {
+        /// <summary>
+        /// Get the previous Guid in array, considering loop of players.
+        /// </summary>
+        /// <param name="gameModel"></param>
+        /// <param name="guids"></param>
+        /// <param name="index"></param>
+        /// <returns></returns>
         public static Guid GetPrev(this IGameModel gameModel, Guid[] guids, int index)
         {
             if (index == 0)
@@ -40,6 +61,13 @@ namespace Koogle.Application.Games
             return guids[index - 1];
         }
 
+        /// <summary>
+        /// Get the next Guid in array, considering loop of players.
+        /// </summary>
+        /// <param name="gameModel"></param>
+        /// <param name="guids"></param>
+        /// <param name="index"></param>
+        /// <returns></returns>
         public static Guid GetNext(this IGameModel gameModel, Guid[] guids, int index)
         {
             if (index == guids.Length - 1)
@@ -49,6 +77,13 @@ namespace Koogle.Application.Games
             return guids[index + 1];
         }
 
+        /// <summary>
+        /// Get the next index in array, considering loop of players.
+        /// </summary>
+        /// <param name="gameModel"></param>
+        /// <param name="guids"></param>
+        /// <param name="index"></param>
+        /// <returns></returns>
         public static int GetNextIndex(this IGameModel gameModel,Guid[] guids, int index)
         {
             if (index == guids.Length - 1)