diff --git a/src/messaging/CredentialApiMessageType.ts b/src/messaging/CredentialApiMessageType.ts
index ac2788a..ac81073 100644
--- a/src/messaging/CredentialApiMessageType.ts
+++ b/src/messaging/CredentialApiMessageType.ts
@@ -104,8 +104,9 @@ export function ensureOwnerIsSender(message: IMessage): void {
  *
  * @param decryptedMessage The decrypted message to check.
  */
-export function verify(decryptedMessage: IMessage): void {
+export function assertKnownMessage(decryptedMessage: IMessage): IMessage['body'] {
   verifyMessageBody(decryptedMessage)
   verifyMessageEnvelope(decryptedMessage)
   ensureOwnerIsSender(decryptedMessage)
+  return decryptedMessage.body
 }
diff --git a/src/tests/index.ts b/src/tests/index.ts
index 68a3e17..bf4c9a1 100644
--- a/src/tests/index.ts
+++ b/src/tests/index.ts
@@ -1,2 +1,9 @@
+/**
+ * Copyright (c) 2018-2023, BOTLabs GmbH.
+ *
+ * This source code is licensed under the BSD 4-Clause "Original" license
+ * found in the LICENSE file in the root directory of this source tree.
+ */
+
 export * from './messageUtils'
 export * from './utils'