RBAC Lookup is a CLI tool for Kubernetes that enables users to find all RoleBindings and ClusterRoleBindings associated with a specific user, service account, or group. The tool connects to a Kubernetes cluster via kubeconfig, queries the RBAC API, and presents the results in a tabular format. It includes optional GKE integration to show Google Cloud IAM roles alongside native Kubernetes RBAC roles. The architecture follows a standard Cobra-based CLI pattern with command definitions in cmd/, core lookup logic in lookup/, and data structures defined in lookup/rbac_subject.go. The tool requires access to a Kubernetes cluster and optionally Google Cloud credentials for GKE features.