diff --git a/src/commonMain/kotlin/ru/landrafhomyak/utility/reference_counter/CloseableReferenceCounter.kt b/src/commonMain/kotlin/ru/landrafhomyak/utility/reference_counter/CloseableReferenceCounter.kt
index ebc959b..0c6edc8 100644
--- a/src/commonMain/kotlin/ru/landrafhomyak/utility/reference_counter/CloseableReferenceCounter.kt
+++ b/src/commonMain/kotlin/ru/landrafhomyak/utility/reference_counter/CloseableReferenceCounter.kt
@@ -1,5 +1,7 @@
 package ru.landrafhomyak.utility.reference_counter
 
+import kotlin.contracts.InvocationKind
+import kotlin.contracts.contract
 import kotlin.jvm.JvmName
 import kotlin.jvm.JvmStatic
 
@@ -13,9 +15,13 @@ public class CloseableReferenceCounter : MayBeClosedReferenceCounter {
 	}
 
 	public companion object {
+		@Suppress("LEAKED_IN_PLACE_LAMBDA", "WRONG_INVOCATION_KIND")
 		@JvmStatic
 		@JvmName("autoClosed")
 		public fun <R> autoClosed(errMessageClosed: String, errExistRefs: String, scope: (MayBeClosedReferenceCounter) -> R): R {
+			contract {
+				callsInPlace(scope, InvocationKind.EXACTLY_ONCE)
+			}
 			_Platform.jvm_assertNotNull(errMessageClosed, "param: errMessageClosed")
 			_Platform.jvm_assertNotNull(errExistRefs, "param: errExistRefs")
 			_Platform.jvm_assertNotNull(scope, "param: scope")