Index: ChapterX.Application/Collaboration/Commands/AddHandler.cs
===================================================================
--- ChapterX.Application/Collaboration/Commands/AddHandler.cs	(revision 877c13c3dd0934c1d31da7988d0d2c2c5925ed55)
+++ ChapterX.Application/Collaboration/Commands/AddHandler.cs	(revision e882b92860e1899312f197af1134bb0f33d30d15)
@@ -22,4 +22,6 @@
                 UserId = request.UserId,
                 StoryId = request.StoryId,
+                Role = request.Role,
+                PermissionLevel = request.PermissionLevel,
                 CreatedAt = DateTime.UtcNow
             };
Index: ChapterX.Application/Collaboration/Commands/AddRequest.cs
===================================================================
--- ChapterX.Application/Collaboration/Commands/AddRequest.cs	(revision 877c13c3dd0934c1d31da7988d0d2c2c5925ed55)
+++ ChapterX.Application/Collaboration/Commands/AddRequest.cs	(revision e882b92860e1899312f197af1134bb0f33d30d15)
@@ -3,4 +3,4 @@
 namespace ChapterX.Application.Collaboration.Commands
 {
-    public record AddRequest(int UserId, int StoryId, string Role) : IRequest<AddResponse>;
+    public record AddRequest(int UserId, int StoryId, string Role, int? PermissionLevel = null) : IRequest<AddResponse>;
 }
Index: ChapterX.Application/Collaboration/Commands/UpdateHandler.cs
===================================================================
--- ChapterX.Application/Collaboration/Commands/UpdateHandler.cs	(revision 877c13c3dd0934c1d31da7988d0d2c2c5925ed55)
+++ ChapterX.Application/Collaboration/Commands/UpdateHandler.cs	(revision e882b92860e1899312f197af1134bb0f33d30d15)
@@ -22,5 +22,6 @@
                 return new UpdateResponse(false);
 
-            // No updatable fields on Collaboration entity
+            collaboration.Role = request.Role;
+            collaboration.PermissionLevel = request.PermissionLevel;
 
             await _collaborationRepository.UpdateAsync(collaboration, cancellationToken);
Index: ChapterX.Application/Collaboration/Commands/UpdateRequest.cs
===================================================================
--- ChapterX.Application/Collaboration/Commands/UpdateRequest.cs	(revision 877c13c3dd0934c1d31da7988d0d2c2c5925ed55)
+++ ChapterX.Application/Collaboration/Commands/UpdateRequest.cs	(revision e882b92860e1899312f197af1134bb0f33d30d15)
@@ -3,4 +3,4 @@
 namespace ChapterX.Application.Collaboration.Commands
 {
-    public record UpdateRequest(int Id, string Role) : IRequest<UpdateResponse>;
+    public record UpdateRequest(int Id, string Role, int? PermissionLevel = null) : IRequest<UpdateResponse>;
 }