diff --git a/mailbox-core/src/test/java/org/briarproject/mailbox/core/TestUtils.kt b/mailbox-core/src/test/java/org/briarproject/mailbox/core/TestUtils.kt
index 23a0b6c77fbc36516e49a97c3b55ad47c2c3bfd7..9ec2c1b1be157711e7f86ff4316e9fb913692c17 100644
--- a/mailbox-core/src/test/java/org/briarproject/mailbox/core/TestUtils.kt
+++ b/mailbox-core/src/test/java/org/briarproject/mailbox/core/TestUtils.kt
@@ -27,6 +27,11 @@ object TestUtils {
         outboxId = getNewRandomId(),
     )
 
+    /**
+     * Allows you to mock [Database] access happening within a [Transaction] more comfortably.
+     * Calls to [Database.transactionWithResult] will be mocked.
+     * The given lambda [block] will get captured and invoked.
+     */
     fun <T> everyTransactionWithResult(db: Database, readOnly: Boolean, block: (Transaction) -> T) {
         val txn = Transaction(mockk(), readOnly)
         every { db.transactionWithResult<T>(true, captureLambda()) } answers {