diff --git a/rules/aws_mq_broker_invalid_engine_type.go b/rules/aws_mq_broker_invalid_engine_type.go
index b832059f..f6203a90 100644
--- a/rules/aws_mq_broker_invalid_engine_type.go
+++ b/rules/aws_mq_broker_invalid_engine_type.go
@@ -19,6 +19,8 @@ func NewAwsMqBrokerInvalidEngineTypeRule() *AwsMqBrokerInvalidEngineTypeRule {
 	return &AwsMqBrokerInvalidEngineTypeRule{
 		resourceType:  "aws_mq_broker",
 		attributeName: "engine_type",
+		// https://docs.aws.amazon.com/amazon-mq/latest/api-reference/broker-engine-types.html
+		// Terraform uses mixed case: ActiveMQ, RabbitMQ (AWS API uses uppercase: ACTIVEMQ, RABBITMQ)
 		enum: []string{
 			"ActiveMQ",
 			"RabbitMQ",
diff --git a/rules/aws_mq_configuration_invalid_engine_type.go b/rules/aws_mq_configuration_invalid_engine_type.go
index 5dc2afd5..a190306f 100644
--- a/rules/aws_mq_configuration_invalid_engine_type.go
+++ b/rules/aws_mq_configuration_invalid_engine_type.go
@@ -19,6 +19,8 @@ func NewAwsMqConfigurationInvalidEngineTypeRule() *AwsMqConfigurationInvalidEngi
 	return &AwsMqConfigurationInvalidEngineTypeRule{
 		resourceType:  "aws_mq_configuration",
 		attributeName: "engine_type",
+		// https://docs.aws.amazon.com/amazon-mq/latest/api-reference/broker-engine-types.html
+		// Terraform uses mixed case: ActiveMQ, RabbitMQ (AWS API uses uppercase: ACTIVEMQ, RABBITMQ)
 		enum: []string{
 			"ActiveMQ",
 			"RabbitMQ",