diff --git a/src/content/docs/aws/services/eks.mdx b/src/content/docs/aws/services/eks.mdx
index 987e002f..468c0b06 100644
--- a/src/content/docs/aws/services/eks.mdx
+++ b/src/content/docs/aws/services/eks.mdx
@@ -686,6 +686,17 @@ The default version is `1.35`.
 
 Users can specify the desired version when creating an EKS cluster in LocalStack using the `EKS_K3S_IMAGE_TAG` configuration variable when starting LocalStack.
 
+## Configuring the k3d Cluster Token
+
+When LocalStack creates a k3d-backed EKS cluster, it starts the k3s server with an explicit cluster token. This token is used to authenticate agent nodes joining the cluster, ensuring consistent behavior across k3d versions and enabling dynamic node registration (for example, when using Karpenter).
+By default, LocalStack uses localstack-k3d-cluster-token as the cluster token. You can override this value using the `EKS_K3D_CLUSTER_TOKEN` configuration variable:
+
+```bash
+EKS_K3D_CLUSTER_TOKEN=my-custom-token localstack start
+```
+
+Any agent nodes added to the cluster — whether via k3d node create or k3s agent — will use the same token to authenticate with the k3s server.
+
 ## Resource Browser
 
 The LocalStack Web Application provides a Resource Browser for managing EKS clusters.