Service interceptors are an extensibility pattern in ArcGIS Enterprise that allows developers to inspect and modify existing service requests and responses at runtime. These lightweight and customizable components can intercept network traffic from any REST-based service published to ArcGIS Enterprise, regardless of its service type. They execute custom business logic and modify the behavior of services by overriding resources or operations in a manner that is seamless to clients, such as ArcGIS Pro and Map Viewer, among others. By providing robust hooks into the request and response lifecycle, service interceptors enable the execution of custom business logic, such as logging, authorization, validation, or data enrichment, at the point of interception. This capability applies across both ArcGIS Enterprise and standalone ArcGIS Server deployments.