The Gremlin Service Mesh Extension, currently in private beta, enhances resilience testing by allowing more granular application-level targeting within service meshes like Istio, which are widely used in dynamic, service-based architectures such as Kubernetes. Traditional infrastructure-based testing targets specific IP addresses, but this approach lacks precision in service mesh environments where IPs frequently change due to their inherent resilience capabilities. The new extension uses the HTTP path for targeting, enabling specific interactions within an application to be tested rather than all traffic from a service, providing a more detailed understanding of application reliability. The beta includes experiments such as Network Latency, Blackhole, and Unexpected Service Response Codes, which can be used to simulate various failure scenarios and validate recovery systems. Compatible with Istio 1.22.x, the extension can be configured via the Gremlin UI or API and promises to enhance the reliability and resilience of service mesh applications without adding extra points of failure.