public ShapeId getOperation() {
        return operation;
    }
The operation used to discover endpoints for the service.

<p>The operation MUST be bound to the service.</p>

@return The ShapeId of the operation used to discover endpoints.
smithy-aws-traits/src/main/java/software/amazon/smithy/aws/traits/clientendpointdiscovery/ClientEndpointDiscoveryTrait.java