diff --git a/src/InternshipSystem.Api/UseCases/UpdateInternshipRegistrationUseCase.cs b/src/InternshipSystem.Api/UseCases/UpdateInternshipRegistrationUseCase.cs
index 10e579c..9f68e67 100644
--- a/src/InternshipSystem.Api/UseCases/UpdateInternshipRegistrationUseCase.cs
+++ b/src/InternshipSystem.Api/UseCases/UpdateInternshipRegistrationUseCase.cs
@@ -30,7 +30,7 @@ namespace InternshipSystem.Api.UseCases
             subjectRegistration = internshipRegistration;
         }
 
-        public async Task<(DocumentState State, IEnumerable<string>)> UpdateInternshipRegistration(
+        public async Task<(DocumentState State, IEnumerable<ErrorDescription>)> UpdateInternshipRegistration(
             UpdateRegistrationForm registrationCommand,
             CancellationToken cancellationToken)
         {
diff --git a/src/InternshipSystem.Core/Entity/Internship/Extensions.cs b/src/InternshipSystem.Core/Entity/Internship/Extensions.cs
new file mode 100644
index 0000000..4aa0001
--- /dev/null
+++ b/src/InternshipSystem.Core/Entity/Internship/Extensions.cs
@@ -0,0 +1,15 @@
+using System.Collections.Generic;
+using System.Linq;
+using FluentValidation.Results;
+using InternshipSystem.Core.Entity.Internship;
+
+namespace InternshipSystem.Core
+{
+    static internal class Extensions
+    {
+        public static IEnumerable<ErrorDescription> ToErrorDescription(this ValidationResult result)
+        {
+            return result.Errors.Select(failure => new ErrorDescription { Key = failure.ErrorCode, Parameters = failure.FormattedMessagePlaceholderValues });
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/InternshipSystem.Core/Entity/Internship/InternshipRegistration.cs b/src/InternshipSystem.Core/Entity/Internship/InternshipRegistration.cs
index 595ab71..119075c 100644
--- a/src/InternshipSystem.Core/Entity/Internship/InternshipRegistration.cs
+++ b/src/InternshipSystem.Core/Entity/Internship/InternshipRegistration.cs
@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Data;
 using System.Linq;
 using FluentValidation;
+using FluentValidation.Results;
 using InternshipSystem.Core.UglyOrmArtifacts;
 
 namespace InternshipSystem.Core.Entity.Internship
@@ -27,7 +28,7 @@ namespace InternshipSystem.Core.Entity.Internship
         }
 
 
-        public (DocumentState State, IEnumerable<string>) ValidateStatus(Edition edition)
+        public (DocumentState State, IEnumerable<ErrorDescription>) ValidateStatus(Edition edition)
         {
             var validator = new Validator(edition);
 
@@ -35,7 +36,7 @@ namespace InternshipSystem.Core.Entity.Internship
 
             State = result.IsValid ? DocumentState.Submitted : DocumentState.Draft;
 
-            return (State, result.Errors.Select(failure => failure.ToString()));
+            return (State, result.ToErrorDescription());
         }
 
         public class Validator : AbstractValidator<InternshipRegistration>
@@ -75,4 +76,10 @@ namespace InternshipSystem.Core.Entity.Internship
             }
         }
     }
+
+    public class ErrorDescription
+    {
+        public string Key { get; set; }
+        public Dictionary<string, object> Parameters { get; set; }
+    }
 }
\ No newline at end of file