diff --git a/src/Kompas.Mcp.Core/Conversion/ConversionService.cs b/src/Kompas.Mcp.Core/Conversion/ConversionService.cs
index 58052e9..0358f0a 100644
--- a/src/Kompas.Mcp.Core/Conversion/ConversionService.cs
+++ b/src/Kompas.Mcp.Core/Conversion/ConversionService.cs
@@ -1,6 +1,6 @@
-using System.Runtime.InteropServices;
 using System.Runtime.Versioning;
 using Kompas.Mcp.Core.Documents;
+using Kompas.Mcp.Core.Interop;
 using Kompas.Mcp.Core.Threading;
 using Kompas6Constants;
 using KompasAPI7;
@@ -39,7 +39,7 @@ public sealed class ConversionService
         CancellationToken ct = default)
         => _dispatcher.InvokeAsync(() => ImportCore(path, docType, createComponentFiles), ct);
 
-    private bool ImportCore(string path, KompasDocumentType docType, bool createComponentFiles)
+    private void ImportCore(string path, KompasDocumentType docType, bool createComponentFiles)
     {
         if (!File.Exists(path))
             throw new FileNotFoundException($"STEP-файл не найден: {path}", path);
@@ -63,19 +63,22 @@ public sealed class ConversionService
             prm.Format = (ksKOMPASConverterEnum)StepFormats.ImportConverterCode;
             if (createComponentFiles)
             {
+                // NeedCreateComponentsFiles может отсутствовать в Home-редакции КОМПАС —
+                // ловим COM-исключения; не критично, если свойство недоступно.
                 try { prm.NeedCreateComponentsFiles = true; }
-                catch { /* свойство может быть недоступно — не критично */ }
+                catch (System.Runtime.InteropServices.COMException) { }
+                catch (System.Runtime.InteropServices.InvalidComObjectException) { }
+                catch (NotImplementedException) { }
             }
 
             if (!doc3d1.ConvertFromAdditionFormat(path, (AdditionConvertParameters)prm))
                 throw new InvalidOperationException("ConvertFromAdditionFormat вернул FALSE (импорт STEP не удался).");
-            return true;
         }
         finally
         {
-            ReleaseCom(prm);
-            ReleaseCom(doc);
-            ReleaseCom(conv);
+            ComHelper.Release(prm);
+            ComHelper.Release(doc);
+            ComHelper.Release(conv);
         }
     }
 
@@ -83,7 +86,7 @@ public sealed class ConversionService
     public Task ExportStepAsync(string path, StepFormat format = StepFormat.Auto, CancellationToken ct = default)
         => _dispatcher.InvokeAsync(() => ExportCore(path, format), ct);
 
-    private bool ExportCore(string path, StepFormat format)
+    private void ExportCore(string path, StepFormat format)
     {
         if (string.IsNullOrWhiteSpace(path))
             throw new ArgumentException("Путь экспорта не задан.", nameof(path));
@@ -109,13 +112,12 @@ public sealed class ConversionService
 
             if (!doc3d1.ConvertToAdditionFormat(path, (AdditionConvertParameters)prm))
                 throw new InvalidOperationException("ConvertToAdditionFormat вернул FALSE (экспорт STEP не удался).");
-            return true;
         }
         finally
         {
-            ReleaseCom(prm);
-            ReleaseCom(active);
-            ReleaseCom(conv);
+            ComHelper.Release(prm);
+            ComHelper.Release(active);
+            ComHelper.Release(conv);
         }
     }
 
@@ -131,13 +133,4 @@ public sealed class ConversionService
         throw new InvalidOperationException(
             $"get_Converter({formatCode}) вернул null — STEP-конвертер недоступен в этой редакции КОМПАС.");
     }
-
-    private static void ReleaseCom(object? comObject)
-    {
-        if (comObject is not null && Marshal.IsComObject(comObject))
-        {
-            try { Marshal.ReleaseComObject(comObject); }
-            catch { /* освобождение не критично */ }
-        }
-    }
 }
diff --git a/src/Kompas.Mcp.Core/Documents/DocumentService.cs b/src/Kompas.Mcp.Core/Documents/DocumentService.cs
index 9eba22e..c3f1363 100644
--- a/src/Kompas.Mcp.Core/Documents/DocumentService.cs
+++ b/src/Kompas.Mcp.Core/Documents/DocumentService.cs
@@ -1,5 +1,5 @@
-using System.Runtime.InteropServices;
 using System.Runtime.Versioning;
+using Kompas.Mcp.Core.Interop;
 using Kompas.Mcp.Core.Threading;
 using Kompas6Constants;
 using KompasAPI7;
@@ -26,7 +26,7 @@ public sealed class DocumentService
             var docs = _session.Application.Documents;
             var doc = (IKompasDocument)docs.Add(DocumentTypes.ToEnum(type), visible);
             try { return ToInfo(doc); }
-            finally { ReleaseCom(doc); ReleaseCom(docs); }
+            finally { ComHelper.Release(doc); ComHelper.Release(docs); }
         }, ct);
 
     /// <summary>Открыть документ с диска.</summary>
@@ -38,7 +38,7 @@ public sealed class DocumentService
             if (doc is null)
                 throw new InvalidOperationException($"Не удалось открыть документ: {path}");
             try { return ToInfo(doc); }
-            finally { ReleaseCom(doc); ReleaseCom(docs); }
+            finally { ComHelper.Release(doc); ComHelper.Release(docs); }
         }, ct);
 
     /// <summary>Сводка по активному документу или <c>null</c>, если документов нет.</summary>
@@ -48,7 +48,7 @@ public sealed class DocumentService
             var doc = _session.Application.ActiveDocument;
             if (doc is null) return null;
             try { return ToInfo(doc); }
-            finally { ReleaseCom(doc); }
+            finally { ComHelper.Release(doc); }
         }, ct);
 
     /// <summary>Сохранить активный документ (для уже сохранённого — без диалога).</summary>
@@ -72,7 +72,7 @@ public sealed class DocumentService
         var doc = _session.Application.ActiveDocument
             ?? throw new InvalidOperationException("Нет активного документа.");
         try { return func(doc); }
-        finally { ReleaseCom(doc); }
+        finally { ComHelper.Release(doc); }
     }
 
     private static DocumentInfo ToInfo(IKompasDocument doc) => new()
@@ -81,13 +81,4 @@ public sealed class DocumentService
         PathName = doc.PathName ?? string.Empty,
         Type = DocumentTypes.FromEnum(doc.DocumentType),
     };
-
-    private static void ReleaseCom(object? comObject)
-    {
-        if (comObject is not null && Marshal.IsComObject(comObject))
-        {
-            try { Marshal.ReleaseComObject(comObject); }
-            catch { /* освобождение не критично */ }
-        }
-    }
 }
diff --git a/src/Kompas.Mcp.Core/Editing/FaceEditService.cs b/src/Kompas.Mcp.Core/Editing/FaceEditService.cs
index 0fcd200..243a7ad 100644
--- a/src/Kompas.Mcp.Core/Editing/FaceEditService.cs
+++ b/src/Kompas.Mcp.Core/Editing/FaceEditService.cs
@@ -28,7 +28,7 @@ public sealed class FaceEditService
     public Task MoveFaceAsync(double x, double y, double z, double distance, CancellationToken ct = default)
         => _dispatcher.InvokeAsync(() => MoveFaceCore(x, y, z, distance), ct);
 
-    private bool MoveFaceCore(double x, double y, double z, double distance)
+    private void MoveFaceCore(double x, double y, double z, double distance)
     {
         if (distance == 0) throw new ArgumentException("Смещение не может быть нулевым.", nameof(distance));
 
@@ -61,7 +61,6 @@ public sealed class FaceEditService
 
         // Перестраиваем, чтобы состояние ошибки операции стало актуальным (проверяется через validate_part).
         doc3d.RebuildDocument();
-        return true;
     }
 
     private static IFace? FindFaceAtPoint(IPart7 part, double x, double y, double z)
diff --git a/src/Kompas.Mcp.Core/Interop/ComHelper.cs b/src/Kompas.Mcp.Core/Interop/ComHelper.cs
new file mode 100644
index 0000000..deb569c
--- /dev/null
+++ b/src/Kompas.Mcp.Core/Interop/ComHelper.cs
@@ -0,0 +1,30 @@
+using System.Runtime.InteropServices;
+
+namespace Kompas.Mcp.Core.Interop;
+
+/// <summary>
+/// Вспомогательные методы для работы с COM RCW: безопасное освобождение
+/// и safe-геттеры для свойств, которые могут бросить исключение.
+/// <para>
+/// Метод <see cref="Release"/> идентично реализован в каждом сервисе — вынесен сюда.
+/// Safe-геттеры заменяют разрозненные <c>SafeStr</c>/<c>SafeGet</c>/<c>SafeBool</c>/<c>SafeNum</c>.
+/// </para>
+/// </summary>
+internal static class ComHelper
+{
+    /// <summary>Освободить COM RCW: null-гард + IsComObject-проверка + try/catch.</summary>
+    internal static void Release(object? com)
+    {
+        if (com is not null && Marshal.IsComObject(com))
+            try { Marshal.ReleaseComObject(com); } catch { }
+    }
+
+    /// <summary>Безопасно получить строку: возвращает <c>""</c> при любом исключении.</summary>
+    internal static string SafeStr(Func<string?> f) { try { return f() ?? ""; } catch { return ""; } }
+
+    /// <summary>Безопасно получить число: возвращает <c>0</c> при любом исключении.</summary>
+    internal static double SafeNum(Func<double> f) { try { return f(); } catch { return 0; } }
+
+    /// <summary>Безопасно получить флаг: возвращает <c>false</c> при любом исключении.</summary>
+    internal static bool SafeBool(Func<bool> f) { try { return f(); } catch { return false; } }
+}
diff --git a/src/Kompas.Mcp.Core/KompasSession.cs b/src/Kompas.Mcp.Core/KompasSession.cs
index b219a04..08962f9 100644
--- a/src/Kompas.Mcp.Core/KompasSession.cs
+++ b/src/Kompas.Mcp.Core/KompasSession.cs
@@ -65,7 +65,7 @@ public sealed class KompasSession : IDisposable
     private KompasConnectionInfo ConnectCore(bool visible)
     {
         if (_app is not null)
-            return LastInfo ??= BuildInfo(LastProgId);
+            return LastInfo ??= BuildInfo(_lastProgId);
 
         // 1) attach к уже запущенному экземпляру
         foreach (var id in ProgIds)
@@ -73,7 +73,7 @@ public sealed class KompasSession : IDisposable
             if (NativeMethods.GetActiveObject(id) is KompasObject ko)
             {
                 _kompas = ko;
-                LastProgId = id;
+                _lastProgId = id;
                 _launchedByUs = false;
                 _log.LogInformation("Присоединились к запущенному КОМПАС ({ProgId})", id);
                 break;
@@ -92,7 +92,7 @@ public sealed class KompasSession : IDisposable
                     if (Activator.CreateInstance(type) is KompasObject ko)
                     {
                         _kompas = ko;
-                        LastProgId = id;
+                        _lastProgId = id;
                         _launchedByUs = true;
                         _log.LogInformation("Запустили новый КОМПАС ({ProgId})", id);
                         break;
@@ -114,10 +114,10 @@ public sealed class KompasSession : IDisposable
 
         _app.Visible = visible;
 
-        return LastInfo = BuildInfo(LastProgId);
+        return LastInfo = BuildInfo(_lastProgId);
     }
 
-    private string LastProgId { get; set; } = string.Empty;
+    private string _lastProgId = string.Empty;
 
     private KompasConnectionInfo BuildInfo(string progId)
     {
diff --git a/src/Kompas.Mcp.Core/Modeling/PartModeler.cs b/src/Kompas.Mcp.Core/Modeling/PartModeler.cs
index bf769f6..d5bdb29 100644
--- a/src/Kompas.Mcp.Core/Modeling/PartModeler.cs
+++ b/src/Kompas.Mcp.Core/Modeling/PartModeler.cs
@@ -1,5 +1,5 @@
-using System.Runtime.InteropServices;
 using System.Runtime.Versioning;
+using Kompas.Mcp.Core.Interop;
 using Kompas.Mcp.Core.Threading;
 using Kompas6API5;
 using Kompas6Constants3D;
@@ -432,14 +432,7 @@ public sealed class PartModeler : IDisposable
         _nextId = 1;
     }
 
-    private static void ReleaseCom(object? comObject)
-    {
-        if (comObject is not null && Marshal.IsComObject(comObject))
-        {
-            try { Marshal.ReleaseComObject(comObject); }
-            catch { /* освобождение не критично */ }
-        }
-    }
+    private static void ReleaseCom(object? comObject) => ComHelper.Release(comObject);
 
     public void Dispose()
     {
diff --git a/src/Kompas.Mcp.Core/Query/GeomClassifiers.cs b/src/Kompas.Mcp.Core/Query/GeomClassifiers.cs
new file mode 100644
index 0000000..2991fd4
--- /dev/null
+++ b/src/Kompas.Mcp.Core/Query/GeomClassifiers.cs
@@ -0,0 +1,39 @@
+using Kompas6API5;
+
+namespace Kompas.Mcp.Core.Query;
+
+/// <summary>
+/// Классификаторы топологических объектов КОМПАС: строковый тип грани и ребра.
+/// <para>
+/// Каждый вызов COM-метода обёрнут в отдельный <c>try/catch</c> — на экзотической геометрии
+/// (NURBS, импортированные STEP-тела) методы класса <c>ksFaceDefinition</c>/<c>ksEdgeDefinition</c>
+/// могут бросить <c>COMException</c>, что не должно прерывать bulk-перебор. Ранее этот код
+/// был продублирован в <c>QueryService</c> (без защиты) и <c>ModelInspectionService</c> (с защитой).
+/// </para>
+/// </summary>
+internal static class GeomClassifiers
+{
+    /// <summary>Строковый тип поверхности: plane/cylinder/cone/sphere/torus/nurbs/other.</summary>
+    internal static string FaceType(ksFaceDefinition d)
+    {
+        try { if (d.IsPlanar()) return "plane"; } catch { }
+        try { if (d.IsCylinder()) return "cylinder"; } catch { }
+        try { if (d.IsCone()) return "cone"; } catch { }
+        try { if (d.IsSphere()) return "sphere"; } catch { }
+        try { if (d.IsTorus()) return "torus"; } catch { }
+        try { if (d.IsNurbsSurface()) return "nurbs"; } catch { }
+        return "other";
+    }
+
+    /// <summary>Строковый тип кривой: line/circle/arc/ellipse_arc/ellipse/nurbs/other.</summary>
+    internal static string EdgeType(ksEdgeDefinition d)
+    {
+        try { if (d.IsLineSeg()) return "line"; } catch { }
+        try { if (d.IsCircle()) return "circle"; } catch { }
+        try { if (d.IsArc()) return "arc"; } catch { }
+        try { if (d.IsEllipseArc()) return "ellipse_arc"; } catch { }
+        try { if (d.IsEllipse()) return "ellipse"; } catch { }
+        try { if (d.IsNurbs()) return "nurbs"; } catch { }
+        return "other";
+    }
+}
diff --git a/src/Kompas.Mcp.Core/Query/InspectionText.cs b/src/Kompas.Mcp.Core/Query/InspectionText.cs
index 9cf8fc8..e7b963c 100644
--- a/src/Kompas.Mcp.Core/Query/InspectionText.cs
+++ b/src/Kompas.Mcp.Core/Query/InspectionText.cs
@@ -23,8 +23,9 @@ public static class InspectionText
     }
 
     // Формообразующие операции, наличие которых означает параметрическую историю.
-    private static readonly string[] OpKinds =
-        { "sketch", "extrusion", "cut_extrusion", "revolve", "cut_revolve", "fillet", "chamfer" };
+    // HashSet<string> даёт O(1) Contains вместо O(n) по массиву при bulk-проверке граней.
+    private static readonly HashSet<string> OpKinds =
+        new(StringComparer.Ordinal) { "sketch", "extrusion", "cut_extrusion", "revolve", "cut_revolve", "fillet", "chamfer" };
 
     /// <summary>
     /// Модель — «голый» импорт без истории построения (типично для STEP): в дереве только начало
@@ -39,18 +40,21 @@ public static class InspectionText
     public static string GroupTypes(IReadOnlyList<string> types)
     {
         if (types.Count == 0) return "—";
+        // Count материализуем один раз: IGrouping<K,V> — IEnumerable без кеша,
+        // двойной вызов g.Count() итерирует группу дважды.
         return string.Join(", ", types
             .GroupBy(t => t)
-            .OrderByDescending(g => g.Count())
-            .ThenBy(g => g.Key, StringComparer.Ordinal)
-            .Select(g => $"{g.Count()} {g.Key}"));
+            .Select(g => (Key: g.Key, Count: g.Count()))
+            .OrderByDescending(x => x.Count)
+            .ThenBy(x => x.Key, StringComparer.Ordinal)
+            .Select(x => $"{x.Count} {x.Key}"));
     }
 
     /// <summary>Отрендерить «паспорт» модели в читаемый текст.</summary>
     public static string Render(ModelDescription d)
     {
         var sb = new StringBuilder();
-        sb.AppendLine($"Документ: «{d.Name}» (деталь)");
+        sb.AppendLine($"Документ: «{d.Name}» ({d.DocumentTypeName})");
 
         if (d.IsEmpty)
         {
diff --git a/src/Kompas.Mcp.Core/Query/ModelDescription.cs b/src/Kompas.Mcp.Core/Query/ModelDescription.cs
index 16603a7..6b7c92c 100644
--- a/src/Kompas.Mcp.Core/Query/ModelDescription.cs
+++ b/src/Kompas.Mcp.Core/Query/ModelDescription.cs
@@ -38,4 +38,10 @@ public sealed record ModelDescription
 
     /// <summary>Переменные модели.</summary>
     public required IReadOnlyList<VariableInfo> Variables { get; init; }
+
+    /// <summary>
+    /// Локализованное название типа документа для вывода: «деталь», «сборка», «чертёж» и т.д.
+    /// По умолчанию «деталь».
+    /// </summary>
+    public string DocumentTypeName { get; init; } = "деталь";
 }
diff --git a/src/Kompas.Mcp.Core/Query/ModelInspectionService.cs b/src/Kompas.Mcp.Core/Query/ModelInspectionService.cs
index ddcc484..0e565fb 100644
--- a/src/Kompas.Mcp.Core/Query/ModelInspectionService.cs
+++ b/src/Kompas.Mcp.Core/Query/ModelInspectionService.cs
@@ -1,6 +1,8 @@
 using System.Globalization;
 using System.Runtime.InteropServices;
 using System.Runtime.Versioning;
+using Kompas.Mcp.Core.Documents;
+using Kompas.Mcp.Core.Interop;
 using Kompas.Mcp.Core.Threading;
 using Kompas6API5;
 using Kompas6Constants3D;
@@ -34,7 +36,7 @@ public sealed class ModelInspectionService
             var part = GetTopPart();
             try
             {
-                var name = ActiveDocName();
+                var (name, typeName) = ActiveDocInfo();
 
                 bool hasGab = part.GetGabarit(false, false,
                     out double x1, out double y1, out double z1, out double x2, out double y2, out double z2);
@@ -48,6 +50,7 @@ public sealed class ModelInspectionService
                         Bodies = Array.Empty<BodyInfo>(), FaceTypes = Array.Empty<string>(),
                         EdgeTypes = Array.Empty<string>(), Features = Array.Empty<FeatureInfo>(),
                         Imported = false, Variables = Array.Empty<VariableInfo>(),
+                        DocumentTypeName = typeName,
                     };
 
                 var bodies = ReadBodies(part);
@@ -67,9 +70,10 @@ public sealed class ModelInspectionService
                     Features = features,
                     Imported = InspectionText.IsImported(features, bodies.Count),
                     Variables = variables,
+                    DocumentTypeName = typeName,
                 };
             }
-            finally { Release(part); }
+            finally { ComHelper.Release(part); }
         }, ct);
 
     /// <summary>Перечислить узлы дерева построения по порядку.</summary>
@@ -78,7 +82,7 @@ public sealed class ModelInspectionService
         {
             var part = GetTopPart();
             try { return ReadFeatures(part); }
-            finally { Release(part); }
+            finally { ComHelper.Release(part); }
         }, ct);
 
     /// <summary>Перечислить тела детали.</summary>
@@ -87,7 +91,7 @@ public sealed class ModelInspectionService
         {
             var part = GetTopPart();
             try { return ReadBodies(part); }
-            finally { Release(part); }
+            finally { ComHelper.Release(part); }
         }, ct);
 
     /// <summary>Перечислить переменные модели.</summary>
@@ -96,7 +100,7 @@ public sealed class ModelInspectionService
         {
             var part = GetTopPart();
             try { return ReadVariables(part); }
-            finally { Release(part); }
+            finally { ComHelper.Release(part); }
         }, ct);
 
     /// <summary>Детали грани по индексу из list_faces: тип, площадь, нормаль, радиус, число рёбер.</summary>
@@ -117,14 +121,14 @@ public sealed class ModelInspectionService
                 return new FaceDetail
                 {
                     Index = index,
-                    Type = FaceType(def),
+                    Type = GeomClassifiers.FaceType(def),
                     Area = area,
                     Normal = FaceNormal(def),
                     Radius = radius,
                     EdgeCount = edgeCount,
                 };
             }
-            finally { Release(part); }
+            finally { ComHelper.Release(part); }
         }, ct);
 
     /// <summary>Детали ребра по индексу из list_edges: тип, длина, смежные грани, концевые вершины.</summary>
@@ -139,13 +143,13 @@ public sealed class ModelInspectionService
 
                 double len = 0; try { len = def.GetLength(MixMm); } catch { }
                 string? f1 = null, f2 = null;
-                try { if (def.GetAdjacentFace(true) is ksFaceDefinition a) f1 = FaceType(a); } catch { }
-                try { if (def.GetAdjacentFace(false) is ksFaceDefinition b) f2 = FaceType(b); } catch { }
+                try { if (def.GetAdjacentFace(true) is ksFaceDefinition a) f1 = GeomClassifiers.FaceType(a); } catch { }
+                try { if (def.GetAdjacentFace(false) is ksFaceDefinition b) f2 = GeomClassifiers.FaceType(b); } catch { }
 
                 return new EdgeDetail
                 {
                     Index = index,
-                    Type = EdgeType(def),
+                    Type = GeomClassifiers.EdgeType(def),
                     Length = len,
                     AdjacentFace1 = f1,
                     AdjacentFace2 = f2,
@@ -153,7 +157,7 @@ public sealed class ModelInspectionService
                     End = Vertex(def, false),
                 };
             }
-            finally { Release(part); }
+            finally { ComHelper.Release(part); }
         }, ct);
 
     /// <summary>
@@ -186,7 +190,7 @@ public sealed class ModelInspectionService
                     AngleValid = angleValid,
                 };
             }
-            finally { Release(part); }
+            finally { ComHelper.Release(part); }
         }, ct);
 
     // ── чтение данных (на STA-потоке) ─────────────────────────────────────
@@ -264,11 +268,11 @@ public sealed class ModelInspectionService
             if (vc.GetByIndex(i) is not ksVariable v) continue;
             list.Add(new VariableInfo
             {
-                Name = SafeStr(() => v.name),
-                Expression = SafeStr(() => v.Expression),
-                Value = SafeNum(() => v.value),
-                External = SafeBool(() => v.external),
-                Information = SafeBool(() => v.Information),
+                Name = ComHelper.SafeStr(() => v.name),
+                Expression = ComHelper.SafeStr(() => v.Expression),
+                Value = ComHelper.SafeNum(() => v.value),
+                External = ComHelper.SafeBool(() => v.external),
+                Information = ComHelper.SafeBool(() => v.Information),
             });
         }
         return list;
@@ -280,10 +284,12 @@ public sealed class ModelInspectionService
         var edgeTypes = new List<string>();
         if (Faces(part) is { } faces)
             for (int i = 0; i < faces.GetCount(); i++)
-                if (faces.GetByIndex(i) is ksEntity e && e.GetDefinition() is ksFaceDefinition d) faceTypes.Add(FaceType(d));
+                if (faces.GetByIndex(i) is ksEntity e && e.GetDefinition() is ksFaceDefinition d)
+                    faceTypes.Add(GeomClassifiers.FaceType(d));
         if (Edges(part) is { } edges)
             for (int i = 0; i < edges.GetCount(); i++)
-                if (edges.GetByIndex(i) is ksEntity e && e.GetDefinition() is ksEdgeDefinition d) edgeTypes.Add(EdgeType(d));
+                if (edges.GetByIndex(i) is ksEntity e && e.GetDefinition() is ksEdgeDefinition d)
+                    edgeTypes.Add(GeomClassifiers.EdgeType(d));
         return (faceTypes, edgeTypes);
     }
 
@@ -349,16 +355,43 @@ public sealed class ModelInspectionService
     {
         var doc3d = _session.Kompas.ActiveDocument3D() as ksDocument3D
             ?? throw new InvalidOperationException("Нет активного 3D-документа.");
-        return doc3d.GetPart((short)Part_Type.pTop_Part) as ksPart
-            ?? throw new InvalidOperationException("Не удалось получить вершинный компонент (ksPart).");
+        // Освобождаем RCW документа сразу после получения ksPart — part имеет собственный ref.
+        try
+        {
+            return doc3d.GetPart((short)Part_Type.pTop_Part) as ksPart
+                ?? throw new InvalidOperationException("Не удалось получить вершинный компонент (ksPart).");
+        }
+        finally { ComHelper.Release(doc3d); }
     }
 
-    private string ActiveDocName()
+    /// <summary>Имя и локализованный тип активного документа. Отдельный API7-вызов от GetTopPart.</summary>
+    private (string name, string typeName) ActiveDocInfo()
     {
         var doc = _session.Application.ActiveDocument;
-        try { return doc?.Name ?? ""; }
-        catch { return ""; }
-        finally { Release(doc); }
+        try
+        {
+            string name = ComHelper.SafeStr(() => doc?.Name);
+            string typeName = "деталь";
+            if (doc is not null)
+            {
+                try
+                {
+                    typeName = DocumentTypes.FromEnum(doc.DocumentType) switch
+                    {
+                        KompasDocumentType.Assembly => "сборка",
+                        KompasDocumentType.Drawing => "чертёж",
+                        KompasDocumentType.Fragment => "фрагмент",
+                        KompasDocumentType.Specification => "спецификация",
+                        KompasDocumentType.Text => "текст",
+                        _ => "деталь",
+                    };
+                }
+                catch { }
+            }
+            return (name, typeName);
+        }
+        catch { return ("", "деталь"); }
+        finally { ComHelper.Release(doc); }
     }
 
     private static ksEntityCollection? Faces(ksPart part) => part.EntityCollection((short)Obj3dType.o3d_face) as ksEntityCollection;
@@ -382,44 +415,11 @@ public sealed class ModelInspectionService
             ?? throw new InvalidOperationException($"Ребро[{index}] не приводится к ksEdgeDefinition.");
     }
 
-    private static string FaceType(ksFaceDefinition d)
-    {
-        try { if (d.IsPlanar()) return "plane"; } catch { }
-        try { if (d.IsCylinder()) return "cylinder"; } catch { }
-        try { if (d.IsCone()) return "cone"; } catch { }
-        try { if (d.IsSphere()) return "sphere"; } catch { }
-        try { if (d.IsTorus()) return "torus"; } catch { }
-        try { if (d.IsNurbsSurface()) return "nurbs"; } catch { }
-        return "other";
-    }
-
-    private static string EdgeType(ksEdgeDefinition d)
-    {
-        try { if (d.IsLineSeg()) return "line"; } catch { }
-        try { if (d.IsCircle()) return "circle"; } catch { }
-        try { if (d.IsArc()) return "arc"; } catch { }
-        try { if (d.IsEllipseArc()) return "ellipse_arc"; } catch { }
-        try { if (d.IsEllipse()) return "ellipse"; } catch { }
-        try { if (d.IsNurbs()) return "nurbs"; } catch { }
-        return "other";
-    }
-
     private static BoundingBox Box(double x1, double y1, double z1, double x2, double y2, double z2) => new()
     {
         MinX = Math.Min(x1, x2), MinY = Math.Min(y1, y2), MinZ = Math.Min(z1, z2),
         MaxX = Math.Max(x1, x2), MaxY = Math.Max(y1, y2), MaxZ = Math.Max(z1, z2),
     };
 
-    private static string SafeStr(Func<string?> g) { try { return g() ?? ""; } catch { return ""; } }
-    private static double SafeNum(Func<double> g) { try { return g(); } catch { return 0; } }
-    private static bool SafeBool(Func<bool> g) { try { return g(); } catch { return false; } }
     private static string Inv(FormattableString fs) => FormattableString.Invariant(fs);
-
-    private static void Release(object? com)
-    {
-        if (com is not null && Marshal.IsComObject(com))
-        {
-            try { Marshal.ReleaseComObject(com); } catch { }
-        }
-    }
 }
diff --git a/src/Kompas.Mcp.Core/Query/QueryService.cs b/src/Kompas.Mcp.Core/Query/QueryService.cs
index b575770..6032731 100644
--- a/src/Kompas.Mcp.Core/Query/QueryService.cs
+++ b/src/Kompas.Mcp.Core/Query/QueryService.cs
@@ -1,5 +1,6 @@
 using System.Runtime.InteropServices;
 using System.Runtime.Versioning;
+using Kompas.Mcp.Core.Interop;
 using Kompas.Mcp.Core.Threading;
 using Kompas6API5;
 using Kompas6Constants3D;
@@ -14,6 +15,9 @@ public sealed class QueryService
     // Иначе КОМПАС вернёт значения в единицах по умолчанию (см/г).
     private const int MixMmKg = 0x1 | 0x10;
 
+    // ST_MIX_MM (0x1) — площади граней / длины рёбер в мм.
+    private const uint MixMm = 0x1;
+
     private readonly KompasSession _session;
     private readonly KompasDispatcher _dispatcher;
 
@@ -33,11 +37,7 @@ public sealed class QueryService
     public Task<PartInfo> GetPartInfoAsync(CancellationToken ct = default)
         => _dispatcher.InvokeAsync(() =>
         {
-            var doc3d = _session.Kompas.ActiveDocument3D() as ksDocument3D
-                ?? throw new InvalidOperationException("Нет активного 3D-документа.");
-            var part = doc3d.GetPart((short)Part_Type.pTop_Part) as ksPart
-                ?? throw new InvalidOperationException("Не удалось получить вершинный компонент (ksPart).");
-
+            var part = GetTopPart();
             ksMassInertiaParam? mass = null;
             try
             {
@@ -56,8 +56,8 @@ public sealed class QueryService
             }
             finally
             {
-                if (mass is not null && Marshal.IsComObject(mass)) Marshal.ReleaseComObject(mass);
-                if (Marshal.IsComObject(part)) Marshal.ReleaseComObject(part);
+                ComHelper.Release(mass);
+                ComHelper.Release(part);
             }
         }, ct);
 
@@ -83,13 +83,22 @@ public sealed class QueryService
                 bool gab = false;
                 try { gab = p.GetGabarit(false, false, out x1, out y1, out z1, out x2, out y2, out z2); }
                 catch { /* габарит может быть недоступен у отдельных компонентов */ }
+
+                // Inline safe-геттеры: избегаем лямбда-аллокаций в горячем цикле по компонентам.
+                string name = "", marking = "", fileName = "";
+                bool isDetail = false;
+                try { name = p.Name ?? ""; } catch { }
+                try { marking = p.Marking ?? ""; } catch { }
+                try { fileName = p.FileName ?? ""; } catch { }
+                try { isDetail = p.Detail; } catch { }
+
                 list.Add(new ComponentInfo
                 {
                     Index = i,
-                    Name = SafeGet(() => p.Name),
-                    Marking = SafeGet(() => p.Marking),
-                    FileName = SafeGet(() => p.FileName),
-                    IsDetail = SafeBool(() => p.Detail),
+                    Name = name,
+                    Marking = marking,
+                    FileName = fileName,
+                    IsDetail = isDetail,
                     SizeX = gab ? Math.Abs(x2 - x1) : 0,
                     SizeY = gab ? Math.Abs(y2 - y1) : 0,
                     SizeZ = gab ? Math.Abs(z2 - z1) : 0,
@@ -98,27 +107,11 @@ public sealed class QueryService
             return list;
         }, ct);
 
-    private static string SafeGet(Func<string?> get)
-    {
-        try { return get() ?? string.Empty; } catch { return string.Empty; }
-    }
-
-    private static bool SafeBool(Func<bool> get)
-    {
-        try { return get(); } catch { return false; }
-    }
-
-    // ST_MIX_MM (0x1) — площади граней в мм².
-    private const uint MixMm = 0x1;
-
     /// <summary>Перечислить грани активной детали: индекс, тип поверхности и площадь (мм²).</summary>
     public Task<IReadOnlyList<FaceInfo>> ListFacesAsync(CancellationToken ct = default)
         => _dispatcher.InvokeAsync<IReadOnlyList<FaceInfo>>(() =>
         {
-            var doc3d = _session.Kompas.ActiveDocument3D() as ksDocument3D
-                ?? throw new InvalidOperationException("Нет активного 3D-документа.");
-            var part = doc3d.GetPart((short)Part_Type.pTop_Part) as ksPart
-                ?? throw new InvalidOperationException("Не удалось получить вершинный компонент (ksPart).");
+            var part = GetTopPart();
             try
             {
                 var faces = part.EntityCollection((short)Obj3dType.o3d_face) as ksEntityCollection
@@ -133,37 +126,20 @@ public sealed class QueryService
                     list.Add(new FaceInfo
                     {
                         Index = i,
-                        Type = FaceType(def),
+                        Type = GeomClassifiers.FaceType(def),
                         Area = def.GetArea(MixMm),
                     });
                 }
                 return list;
             }
-            finally
-            {
-                if (Marshal.IsComObject(part)) Marshal.ReleaseComObject(part);
-            }
+            finally { ComHelper.Release(part); }
         }, ct);
 
-    private static string FaceType(ksFaceDefinition def)
-    {
-        if (def.IsPlanar()) return "plane";
-        if (def.IsCylinder()) return "cylinder";
-        if (def.IsCone()) return "cone";
-        if (def.IsSphere()) return "sphere";
-        if (def.IsTorus()) return "torus";
-        if (def.IsNurbsSurface()) return "nurbs";
-        return "other";
-    }
-
     /// <summary>Перечислить рёбра активной детали: индекс, тип кривой и длину (мм).</summary>
     public Task<IReadOnlyList<EdgeInfo>> ListEdgesAsync(CancellationToken ct = default)
         => _dispatcher.InvokeAsync<IReadOnlyList<EdgeInfo>>(() =>
         {
-            var doc3d = _session.Kompas.ActiveDocument3D() as ksDocument3D
-                ?? throw new InvalidOperationException("Нет активного 3D-документа.");
-            var part = doc3d.GetPart((short)Part_Type.pTop_Part) as ksPart
-                ?? throw new InvalidOperationException("Не удалось получить вершинный компонент (ksPart).");
+            var part = GetTopPart();
             try
             {
                 var edges = part.EntityCollection((short)Obj3dType.o3d_edge) as ksEntityCollection
@@ -178,37 +154,20 @@ public sealed class QueryService
                     list.Add(new EdgeInfo
                     {
                         Index = i,
-                        Type = EdgeType(def),
+                        Type = GeomClassifiers.EdgeType(def),
                         Length = def.GetLength(MixMm),
                     });
                 }
                 return list;
             }
-            finally
-            {
-                if (Marshal.IsComObject(part)) Marshal.ReleaseComObject(part);
-            }
+            finally { ComHelper.Release(part); }
         }, ct);
 
-    private static string EdgeType(ksEdgeDefinition def)
-    {
-        if (def.IsLineSeg()) return "line";
-        if (def.IsCircle()) return "circle";
-        if (def.IsArc()) return "arc";
-        if (def.IsEllipseArc()) return "ellipse_arc";
-        if (def.IsEllipse()) return "ellipse";
-        if (def.IsNurbs()) return "nurbs";
-        return "other";
-    }
-
     /// <summary>Габаритный параллелепипед активной детали (по телам), мм.</summary>
     public Task<BoundingBox> GetBoundingBoxAsync(CancellationToken ct = default)
         => _dispatcher.InvokeAsync(() =>
         {
-            var doc3d = _session.Kompas.ActiveDocument3D() as ksDocument3D
-                ?? throw new InvalidOperationException("Нет активного 3D-документа.");
-            var part = doc3d.GetPart((short)Part_Type.pTop_Part) as ksPart
-                ?? throw new InvalidOperationException("Не удалось получить вершинный компонент (ksPart).");
+            var part = GetTopPart();
             try
             {
                 // full=false → только тела (без вспомогательной геометрии); customizable игнорируется.
@@ -223,9 +182,24 @@ public sealed class QueryService
                     MaxX = Math.Max(x1, x2), MaxY = Math.Max(y1, y2), MaxZ = Math.Max(z1, z2),
                 };
             }
-            finally
-            {
-                if (Marshal.IsComObject(part)) Marshal.ReleaseComObject(part);
-            }
+            finally { ComHelper.Release(part); }
         }, ct);
+
+    // ── низкоуровневые помощники ──────────────────────────────────────────
+
+    /// <summary>
+    /// Получить вершинный компонент активной детали. Освобождает RCW doc3d сразу после
+    /// GetPart — ksPart имеет собственный COM-счётчик ссылок.
+    /// </summary>
+    private ksPart GetTopPart()
+    {
+        var doc3d = _session.Kompas.ActiveDocument3D() as ksDocument3D
+            ?? throw new InvalidOperationException("Нет активного 3D-документа.");
+        try
+        {
+            return doc3d.GetPart((short)Part_Type.pTop_Part) as ksPart
+                ?? throw new InvalidOperationException("Не удалось получить вершинный компонент (ksPart).");
+        }
+        finally { ComHelper.Release(doc3d); }
+    }
 }
diff --git a/src/Kompas.Mcp.Core/Vision/RasterImageFormat.cs b/src/Kompas.Mcp.Core/Vision/RasterImageFormat.cs
index 27357fc..f1cedcb 100644
--- a/src/Kompas.Mcp.Core/Vision/RasterImageFormat.cs
+++ b/src/Kompas.Mcp.Core/Vision/RasterImageFormat.cs
@@ -25,6 +25,18 @@ public static class RasterImageFormats
         _ => "application/octet-stream",
     };
 
+    /// <summary>Расширение файла без точки — постоянная строка без аллокации (в отличие от ToString().ToLower()).</summary>
+    public static string FileExtension(this RasterImageFormat format) => format switch
+    {
+        RasterImageFormat.Bmp => "bmp",
+        RasterImageFormat.Gif => "gif",
+        RasterImageFormat.Jpg => "jpg",
+        RasterImageFormat.Png => "png",
+        RasterImageFormat.Tif => "tif",
+        RasterImageFormat.Tga => "tga",
+        _ => format.ToString().ToLowerInvariant(),
+    };
+
     public static RasterImageFormat Parse(string value) => value.Trim().ToLowerInvariant() switch
     {
         "png" => RasterImageFormat.Png,
diff --git a/src/Kompas.Mcp.Core/Vision/SnapshotService.cs b/src/Kompas.Mcp.Core/Vision/SnapshotService.cs
index d839ca7..00942d0 100644
--- a/src/Kompas.Mcp.Core/Vision/SnapshotService.cs
+++ b/src/Kompas.Mcp.Core/Vision/SnapshotService.cs
@@ -64,7 +64,7 @@ public sealed class SnapshotService
         param.returnResultAsArrayBytes = false;
 
         var outFile = saveToFile ?? Path.Combine(
-            Path.GetTempPath(), $"kompas-snap-{Guid.NewGuid():N}.{format.ToString().ToLowerInvariant()}");
+            Path.GetTempPath(), $"kompas-snap-{Guid.NewGuid():N}.{format.FileExtension()}");
         var deleteAfter = saveToFile is null;
 
         try