diff --git a/BizHawk.Client.EmuHawk/tools/ToolManager.cs b/BizHawk.Client.EmuHawk/tools/ToolManager.cs
index 1d4f348f0f..18dc99da8a 100644
--- a/BizHawk.Client.EmuHawk/tools/ToolManager.cs
+++ b/BizHawk.Client.EmuHawk/tools/ToolManager.cs
@@ -728,60 +728,33 @@ namespace BizHawk.Client.EmuHawk
 			}
 		}
 
-		public bool IsAvailable<T>()
-		{
-			return IsAvailable(typeof(T));
-		}
+		private static readonly Lazy<Type[]> lazyAsmTypes = new Lazy<Type[]>(() => Assembly.ReflectionOnlyLoadFrom(Assembly.GetExecutingAssembly().Location).GetTypes());
 
-		public bool IsAvailable(Type t)
+		public bool IsAvailable(Type tool)
 		{
-			if (!ServiceInjector.IsAvailable(Global.Emulator.ServiceProvider, t))
+			if (!ServiceInjector.IsAvailable(Global.Emulator.ServiceProvider, tool)
+				|| (tool == typeof(LuaConsole) && PlatformLinkedLibSingleton.RunningOnUnix) // simply doesn't work (for now)
+				|| !Array.Exists(lazyAsmTypes.Value, t => t == tool)) // not a tool
 			{
 				return false;
 			}
 
-			if (t == typeof(LuaConsole) && PlatformLinkedLibSingleton.RunningOnUnix) return false;
-
-			var tool = Assembly
-					.GetExecutingAssembly()
-					.GetTypes()
-					.FirstOrDefault(type => type == t);
-
-			if (tool == null) // This isn't a tool, must not be available
+			ToolAttribute attr;
+			try
 			{
-				return false;
+				attr = tool.GetCustomAttributes(false).OfType<ToolAttribute>().Single();
 			}
-
-			var attr = tool.GetCustomAttributes(false)
-				.OfType<ToolAttribute>()
-				.FirstOrDefault();
-
-            // start with the assumption that if no supported systems are mentioned and no unsupported cores are mentioned
-            // then this is available for all
-            bool supported = true;
-            
-            if (attr?.SupportedSystems != null && attr.SupportedSystems.Any())
+			catch (InvalidOperationException e) // no ToolAttribute on given type
 			{
-                // supported systems are available
-                supported = attr.SupportedSystems.Contains(Global.Emulator.SystemId);
-
-                if (supported)
-                {
-                    // check for a core not supported override
-                    if (attr.UnsupportedCores.Contains(Global.Emulator.DisplayName()))
-                        supported = false; 
-                }
+				return true;
 			}
-            else if (attr?.UnsupportedCores != null && attr.UnsupportedCores.Any())
-            {
-                // no supported system specified, but unsupported cores are
-                if (attr.UnsupportedCores.Contains(Global.Emulator.DisplayName()))
-                    supported = false;
-            }
-
-			return supported;
+			var sysName = Global.Emulator.DisplayName();
+			return !attr.UnsupportedCores.Contains(sysName) // not unsupported
+				&& (!attr.SupportedSystems.Any() || attr.SupportedSystems.Contains(sysName)); // supported (no supported list -> assumed all supported)
 		}
 
+		public bool IsAvailable<T>() => IsAvailable(typeof(T));
+
 		// Note: Referencing these properties creates an instance of the tool and persists it.  They should be referenced by type if this is not desired
 		#region Tools