diff --git a/src/Serval.Shared/Controllers/FailedPreconditionRpcExceptionFilter.cs b/src/Serval.Shared/Controllers/FailedPreconditionRpcExceptionFilter.cs
new file mode 100644
index 00000000..160eb9a6
--- /dev/null
+++ b/src/Serval.Shared/Controllers/FailedPreconditionRpcExceptionFilter.cs
@@ -0,0 +1,13 @@
+namespace Serval.Shared.Controllers;
+
+public class FailedPreconditionRpcExceptionFilter : ExceptionFilterAttribute
+{
+    public override void OnException(ExceptionContext context)
+    {
+        if (context.Exception is RpcException rpcException && rpcException.StatusCode == StatusCode.FailedPrecondition)
+        {
+            context.Result = new ConflictObjectResult(rpcException.Message);
+            context.ExceptionHandled = true;
+        }
+    }
+}
diff --git a/src/Serval.Shared/Controllers/ServalControllerBase.cs b/src/Serval.Shared/Controllers/ServalControllerBase.cs
index bebcdf29..08adbf54 100644
--- a/src/Serval.Shared/Controllers/ServalControllerBase.cs
+++ b/src/Serval.Shared/Controllers/ServalControllerBase.cs
@@ -7,6 +7,7 @@
 [TypeFilter(typeof(ServiceUnavailableExceptionFilter))]
 [TypeFilter(typeof(ErrorResultFilter))]
 [TypeFilter(typeof(AbortedRpcExceptionFilter))]
+[TypeFilter(typeof(FailedPreconditionRpcExceptionFilter))]
 public abstract class ServalControllerBase : Controller
 {
     private readonly IAuthorizationService _authService;
diff --git a/src/Serval.Translation/Controllers/TranslationEnginesController.cs b/src/Serval.Translation/Controllers/TranslationEnginesController.cs
index d3f6ab25..8f86ccb3 100644
--- a/src/Serval.Translation/Controllers/TranslationEnginesController.cs
+++ b/src/Serval.Translation/Controllers/TranslationEnginesController.cs
@@ -216,17 +216,7 @@ CancellationToken cancellationToken
         if (!(await AuthorizeAsync(id, cancellationToken)).IsSuccess(out ActionResult? errorResult))
             return errorResult;
 
-        TranslationResult? result;
-        try
-        {
-            result = await _engineService.TranslateAsync(id, segment, cancellationToken);
-        }
-        catch (RpcException r)
-        {
-            if (r.StatusCode == Grpc.Core.StatusCode.FailedPrecondition)
-                return Conflict();
-            throw;
-        }
+        TranslationResult? result = await _engineService.TranslateAsync(id, segment, cancellationToken);
         if (result == null)
             return NotFound();
         return Ok(Map(result));
@@ -267,17 +257,13 @@ CancellationToken cancellationToken
         if (!(await AuthorizeAsync(id, cancellationToken)).IsSuccess(out ActionResult? errorResult))
             return errorResult;
 
-        IEnumerable<TranslationResult>? results;
-        try
-        {
-            results = await _engineService.TranslateAsync(id, n, segment, cancellationToken);
-        }
-        catch (RpcException r)
-        {
-            if (r.StatusCode == Grpc.Core.StatusCode.FailedPrecondition)
-                return Conflict();
-            throw;
-        }
+        IEnumerable<TranslationResult>? results = await _engineService.TranslateAsync(
+            id,
+            n,
+            segment,
+            cancellationToken
+        );
+
         if (results == null)
             return NotFound();
         return Ok(results.Select(Map));
@@ -315,17 +301,8 @@ CancellationToken cancellationToken
     {
         if (!(await AuthorizeAsync(id, cancellationToken)).IsSuccess(out ActionResult? errorResult))
             return errorResult;
-        WordGraph? wordGraph;
-        try
-        {
-            wordGraph = await _engineService.GetWordGraphAsync(id, segment, cancellationToken);
-        }
-        catch (RpcException r)
-        {
-            if (r.StatusCode == Grpc.Core.StatusCode.FailedPrecondition)
-                return Conflict();
-            throw;
-        }
+        WordGraph? wordGraph = await _engineService.GetWordGraphAsync(id, segment, cancellationToken);
+
         if (wordGraph == null)
             return NotFound();
         return Ok(Map(wordGraph));