diff --git a/ArchiSteamFarm/IPC/Integration/CustomAttributesSchemaFilter.cs b/ArchiSteamFarm/IPC/Integration/CustomAttributesSchemaFilter.cs
index ba742fef0..07195c69e 100644
--- a/ArchiSteamFarm/IPC/Integration/CustomAttributesSchemaFilter.cs
+++ b/ArchiSteamFarm/IPC/Integration/CustomAttributesSchemaFilter.cs
@@ -41,9 +41,9 @@ namespace ArchiSteamFarm.IPC.Integration {
 				return;
 			}
 
-			context.MemberInfo.GetCustomAttribute<SwaggerItemsMinMaxAttribute>()?.Apply(schema);
-			context.MemberInfo.GetCustomAttribute<SwaggerSteamIdentifierAttribute>()?.Apply(schema);
-			context.MemberInfo.GetCustomAttribute<SwaggerValidValuesAttribute>()?.Apply(schema);
+			foreach (CustomSwaggerAttribute customSwaggerAttribute in context.MemberInfo.GetCustomAttributes<CustomSwaggerAttribute>()) {
+				customSwaggerAttribute.Apply(schema);
+			}
 		}
 	}
 }
diff --git a/ArchiSteamFarm/IPC/Integration/CustomSwaggerAttribute.cs b/ArchiSteamFarm/IPC/Integration/CustomSwaggerAttribute.cs
new file mode 100644
index 000000000..df2db1d61
--- /dev/null
+++ b/ArchiSteamFarm/IPC/Integration/CustomSwaggerAttribute.cs
@@ -0,0 +1,31 @@
+//     _                _      _  ____   _                           _____
+//    / \    _ __  ___ | |__  (_)/ ___| | |_  ___   __ _  _ __ ___  |  ___|__ _  _ __  _ __ ___
+//   / _ \  | '__|/ __|| '_ \ | |\___ \ | __|/ _ \ / _` || '_ ` _ \ | |_  / _` || '__|| '_ ` _ \
+//  / ___ \ | |  | (__ | | | || | ___) || |_|  __/| (_| || | | | | ||  _|| (_| || |   | | | | | |
+// /_/   \_\|_|   \___||_| |_||_||____/  \__|\___| \__,_||_| |_| |_||_|   \__,_||_|   |_| |_| |_|
+// |
+// Copyright 2015-2021 Łukasz "JustArchi" Domeradzki
+// Contact: JustArchi@JustArchi.net
+// |
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// |
+// http://www.apache.org/licenses/LICENSE-2.0
+// |
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System;
+using JetBrains.Annotations;
+using Microsoft.OpenApi.Models;
+
+namespace ArchiSteamFarm.IPC.Integration {
+	[PublicAPI]
+	public abstract class CustomSwaggerAttribute : Attribute {
+		public abstract void Apply(OpenApiSchema schema);
+	}
+}
diff --git a/ArchiSteamFarm/IPC/Integration/SwaggerItemsMinMaxAttribute.cs b/ArchiSteamFarm/IPC/Integration/SwaggerItemsMinMaxAttribute.cs
index 669c98775..ab212ff21 100644
--- a/ArchiSteamFarm/IPC/Integration/SwaggerItemsMinMaxAttribute.cs
+++ b/ArchiSteamFarm/IPC/Integration/SwaggerItemsMinMaxAttribute.cs
@@ -20,14 +20,13 @@
 // limitations under the License.
 
 using System;
-using System.ComponentModel.DataAnnotations;
 using JetBrains.Annotations;
 using Microsoft.OpenApi.Models;
 
 namespace ArchiSteamFarm.IPC.Integration {
 	[AttributeUsage(AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property)]
 	[PublicAPI]
-	public sealed class SwaggerItemsMinMaxAttribute : ValidationAttribute {
+	public sealed class SwaggerItemsMinMaxAttribute : CustomSwaggerAttribute {
 		public uint MaximumUint {
 			get => BackingMaximum.HasValue ? decimal.ToUInt32(BackingMaximum.Value) : default(uint);
 			set => BackingMaximum = value;
@@ -41,7 +40,7 @@ namespace ArchiSteamFarm.IPC.Integration {
 		private decimal? BackingMaximum;
 		private decimal? BackingMinimum;
 
-		public void Apply(OpenApiSchema schema) {
+		public override void Apply(OpenApiSchema schema) {
 			if (schema == null) {
 				throw new ArgumentNullException(nameof(schema));
 			}
diff --git a/ArchiSteamFarm/IPC/Integration/SwaggerSteamIdentifierAttribute.cs b/ArchiSteamFarm/IPC/Integration/SwaggerSteamIdentifierAttribute.cs
index 56af37bf9..77ab3a64f 100644
--- a/ArchiSteamFarm/IPC/Integration/SwaggerSteamIdentifierAttribute.cs
+++ b/ArchiSteamFarm/IPC/Integration/SwaggerSteamIdentifierAttribute.cs
@@ -20,7 +20,6 @@
 // limitations under the License.
 
 using System;
-using System.ComponentModel.DataAnnotations;
 using JetBrains.Annotations;
 using Microsoft.OpenApi.Models;
 using SteamKit2;
@@ -28,13 +27,13 @@ using SteamKit2;
 namespace ArchiSteamFarm.IPC.Integration {
 	[AttributeUsage(AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property)]
 	[PublicAPI]
-	public sealed class SwaggerSteamIdentifierAttribute : ValidationAttribute {
+	public sealed class SwaggerSteamIdentifierAttribute : CustomSwaggerAttribute {
 		public EAccountType AccountType { get; set; } = EAccountType.Individual;
 		public uint MaximumAccountID { get; set; } = uint.MaxValue;
 		public uint MinimumAccountID { get; set; } = 1;
 		public EUniverse Universe { get; set; } = EUniverse.Public;
 
-		public void Apply(OpenApiSchema schema) {
+		public override void Apply(OpenApiSchema schema) {
 			if (schema == null) {
 				throw new ArgumentNullException(nameof(schema));
 			}
diff --git a/ArchiSteamFarm/IPC/Integration/SwaggerValidValuesAttribute.cs b/ArchiSteamFarm/IPC/Integration/SwaggerValidValuesAttribute.cs
index 336c96ff9..d3bee9425 100644
--- a/ArchiSteamFarm/IPC/Integration/SwaggerValidValuesAttribute.cs
+++ b/ArchiSteamFarm/IPC/Integration/SwaggerValidValuesAttribute.cs
@@ -20,7 +20,6 @@
 // limitations under the License.
 
 using System;
-using System.ComponentModel.DataAnnotations;
 using System.Linq;
 using JetBrains.Annotations;
 using Microsoft.OpenApi.Any;
@@ -30,11 +29,11 @@ using Microsoft.OpenApi.Models;
 namespace ArchiSteamFarm.IPC.Integration {
 	[AttributeUsage(AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property)]
 	[PublicAPI]
-	public sealed class SwaggerValidValuesAttribute : ValidationAttribute {
+	public sealed class SwaggerValidValuesAttribute : CustomSwaggerAttribute {
 		public int[]? ValidIntValues { get; set; }
 		public string[]? ValidStringValues { get; set; }
 
-		public void Apply(OpenApiSchema schema) {
+		public override void Apply(OpenApiSchema schema) {
 			if (schema == null) {
 				throw new ArgumentNullException(nameof(schema));
 			}