diff --git a/DiunaBI.API/Attributes/ApiKeyAuthAttribute.cs b/DiunaBI.API/Attributes/ApiKeyAuthAttribute.cs
new file mode 100644
index 0000000..f911748
--- /dev/null
+++ b/DiunaBI.API/Attributes/ApiKeyAuthAttribute.cs
@@ -0,0 +1,63 @@
+using System.Security.Cryptography;
+using System.Text;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Filters;
+
+namespace DiunaBI.API.Attributes;
+
+/// <summary>
+/// Authorization attribute that validates API key from X-API-Key header.
+/// Uses constant-time comparison to prevent timing attacks.
+/// </summary>
+[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
+public class ApiKeyAuthAttribute : Attribute, IAuthorizationFilter
+{
+    private const string ApiKeyHeaderName = "X-API-Key";
+
+    public void OnAuthorization(AuthorizationFilterContext context)
+    {
+        var configuration = context.HttpContext.RequestServices.GetRequiredService<IConfiguration>();
+        var logger = context.HttpContext.RequestServices.GetRequiredService<ILogger<ApiKeyAuthAttribute>>();
+
+        // Get expected API key from configuration
+        var expectedApiKey = configuration["apiKey"];
+        if (string.IsNullOrEmpty(expectedApiKey))
+        {
+            logger.LogError("API key not configured in appsettings");
+            context.Result = new StatusCodeResult(StatusCodes.Status500InternalServerError);
+            return;
+        }
+
+        // Get API key from header
+        if (!context.HttpContext.Request.Headers.TryGetValue(ApiKeyHeaderName, out var extractedApiKey))
+        {
+            logger.LogWarning("API key missing from request header");
+            context.Result = new UnauthorizedObjectResult(new { error = "API key is required" });
+            return;
+        }
+
+        // Constant-time comparison to prevent timing attacks
+        if (!IsApiKeyValid(extractedApiKey!, expectedApiKey))
+        {
+            logger.LogWarning("Invalid API key provided from {RemoteIp}", context.HttpContext.Connection.RemoteIpAddress);
+            context.Result = new UnauthorizedObjectResult(new { error = "Invalid API key" });
+            return;
+        }
+
+        // API key is valid - allow the request to proceed
+    }
+
+    /// <summary>
+    /// Constant-time string comparison to prevent timing attacks.
+    /// </summary>
+    private static bool IsApiKeyValid(string providedKey, string expectedKey)
+    {
+        if (providedKey == null || expectedKey == null)
+            return false;
+
+        var providedBytes = Encoding.UTF8.GetBytes(providedKey);
+        var expectedBytes = Encoding.UTF8.GetBytes(expectedKey);
+
+        return CryptographicOperations.FixedTimeEquals(providedBytes, expectedBytes);
+    }
+}
diff --git a/DiunaBI.API/Controllers/DataInboxController.cs b/DiunaBI.API/Controllers/DataInboxController.cs
index cf113f4..9ad6ab3 100644
--- a/DiunaBI.API/Controllers/DataInboxController.cs
+++ b/DiunaBI.API/Controllers/DataInboxController.cs
@@ -87,7 +87,7 @@ public class DataInboxController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "DataInbox: Insert error for source {Source}, name {Name}", dataInbox.Source, dataInbox.Name);
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -137,7 +137,7 @@ public class DataInboxController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "GetAll: Error retrieving data inbox items");
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -172,7 +172,7 @@ public class DataInboxController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "Get: Error retrieving data inbox item {Id}", id);
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
diff --git a/DiunaBI.API/Controllers/JobsController.cs b/DiunaBI.API/Controllers/JobsController.cs
index e95fad0..4fa0a3b 100644
--- a/DiunaBI.API/Controllers/JobsController.cs
+++ b/DiunaBI.API/Controllers/JobsController.cs
@@ -1,3 +1,4 @@
+using DiunaBI.API.Attributes;
 using DiunaBI.Application.DTOModels.Common;
 using DiunaBI.Domain.Entities;
 using DiunaBI.Infrastructure.Data;
@@ -82,7 +83,7 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "GetAll: Error retrieving jobs");
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred while retrieving jobs");
         }
     }
 
@@ -108,21 +109,15 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "Get: Error retrieving job {JobId}", id);
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
     [HttpPost]
-    [Route("schedule/{apiKey}")]
-    [AllowAnonymous]
-    public async Task<IActionResult> ScheduleJobs(string apiKey, [FromQuery] string? nameFilter = null)
+    [Route("schedule")]
+    [ApiKeyAuth]
+    public async Task<IActionResult> ScheduleJobs([FromQuery] string? nameFilter = null)
     {
-        if (apiKey != _configuration["apiKey"])
-        {
-            _logger.LogWarning("ScheduleJobs: Unauthorized request with apiKey {ApiKey}", apiKey);
-            return Unauthorized();
-        }
-
         try
         {
             var jobsCreated = await _jobScheduler.ScheduleAllJobsAsync(nameFilter);
@@ -139,21 +134,15 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "ScheduleJobs: Error scheduling jobs");
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
     [HttpPost]
-    [Route("schedule/imports/{apiKey}")]
-    [AllowAnonymous]
-    public async Task<IActionResult> ScheduleImportJobs(string apiKey, [FromQuery] string? nameFilter = null)
+    [Route("schedule/imports")]
+    [ApiKeyAuth]
+    public async Task<IActionResult> ScheduleImportJobs([FromQuery] string? nameFilter = null)
     {
-        if (apiKey != _configuration["apiKey"])
-        {
-            _logger.LogWarning("ScheduleImportJobs: Unauthorized request with apiKey {ApiKey}", apiKey);
-            return Unauthorized();
-        }
-
         try
         {
             var jobsCreated = await _jobScheduler.ScheduleImportJobsAsync(nameFilter);
@@ -170,21 +159,15 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "ScheduleImportJobs: Error scheduling import jobs");
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
     [HttpPost]
-    [Route("schedule/processes/{apiKey}")]
-    [AllowAnonymous]
-    public async Task<IActionResult> ScheduleProcessJobs(string apiKey)
+    [Route("schedule/processes")]
+    [ApiKeyAuth]
+    public async Task<IActionResult> ScheduleProcessJobs()
     {
-        if (apiKey != _configuration["apiKey"])
-        {
-            _logger.LogWarning("ScheduleProcessJobs: Unauthorized request with apiKey {ApiKey}", apiKey);
-            return Unauthorized();
-        }
-
         try
         {
             var jobsCreated = await _jobScheduler.ScheduleProcessJobsAsync();
@@ -201,7 +184,7 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "ScheduleProcessJobs: Error scheduling process jobs");
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -243,7 +226,7 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "RetryJob: Error retrying job {JobId}", id);
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -290,7 +273,7 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "CancelJob: Error cancelling job {JobId}", id);
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -317,7 +300,7 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "GetStats: Error retrieving job statistics");
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -429,7 +412,7 @@ public class JobsController : Controller
         catch (Exception ex)
         {
             _logger.LogError(ex, "CreateJobForLayer: Error creating job for layer {LayerId}", layerId);
-            return BadRequest(ex.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 }
diff --git a/DiunaBI.API/Controllers/LayersController.cs b/DiunaBI.API/Controllers/LayersController.cs
index 353b71f..0c3a958 100644
--- a/DiunaBI.API/Controllers/LayersController.cs
+++ b/DiunaBI.API/Controllers/LayersController.cs
@@ -99,7 +99,7 @@ public class LayersController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "GetAll: Error retrieving layers");
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
     [HttpGet]
@@ -119,7 +119,7 @@ public class LayersController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "Get: Error retrieving layer {LayerId}", id);
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
     [HttpGet]
@@ -396,7 +396,7 @@ public class LayersController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "AutoImport: Process error");
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -808,7 +808,7 @@ public class LayersController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "CreateRecord: Error creating record in layer {LayerId}", layerId);
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -889,7 +889,7 @@ public class LayersController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "UpdateRecord: Error updating record {RecordId} in layer {LayerId}", recordId, layerId);
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -944,7 +944,7 @@ public class LayersController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "DeleteRecord: Error deleting record {RecordId} from layer {LayerId}", recordId, layerId);
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -983,7 +983,7 @@ public class LayersController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "GetRecordHistory: Error retrieving history for record {RecordId}", recordId);
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }
 
@@ -1033,7 +1033,7 @@ public class LayersController : Controller
         catch (Exception e)
         {
             _logger.LogError(e, "GetDeletedRecords: Error retrieving deleted records for layer {LayerId}", layerId);
-            return BadRequest(e.ToString());
+            return BadRequest("An error occurred processing your request");
         }
     }