Create a Sandbox with VSCode and Gemini CLI

Apply the sandbox manifest with PVC

kubectl apply -k base

They can then check the status of the applied resource. Verify sandbox and pod are running:

kubectl get sandbox
kubectl get pod sandbox-example

kubectl wait --for=condition=Ready sandbox sandbox-example

Harden Agent Sandbox isolation using gVisor (Optional)

The Sandbox API provides lifecycle features that are useful for managing long running sandbox workloads on kubernetes. In real world scenarios, you may want to also provide workload isolation for running untrusted workloads inside a sandbox.

gVisor provides a virtualization layer between applications and the host operating system that creates a strong layer of isolation. It implements the kernel in userspace and minimizes the risk of a workload gaining access to the host machine.

This example demonstrates how to use Sandbox along with gVisor in order to utilize the lifecycle features of Sandbox in addition with the workload isolation features of gVisor.

Create a cluster with gVisor enabled

First, enable gVisor on your Kubernetes cluster. For examples of how to enable gVisor, see the gVisor documentation.

Create a Sandbox using the gVisor runtimeClassName

Apply the kustomize overlay to inject runtimeClassName: gvisor to the vscode-sandbox example and apply it to the cluster:

kubectl apply -k overlays/gvisor

Validate that the Pod with gVisor enabled is running:

$ kubectl wait --for=condition=Ready sandbox sandbox-example
$ kubectl get pods -o jsonpath=$'{range .items[*]}{.metadata.name}: {.spec.runtimeClassName}\n{end}'

Harden Agent Sandbox isolation using Kata Containers (Optional)

Prerequisites

• Host machine that supports nested virtualization

  You can verify that by running:

  cat /sys/module/kvm_intel/parameters/nested
  

  In case of AMD platform replace kvm_intel with kvm_amd The output must be “Y” or 1.

• minikube

• kubectl

Create minikube cluster

Note: At this moment, we use only containerd runtime, since it works without additional adjustments.

minikube start --vm-driver kvm2 --memory 8192  --container-runtime=containerd --bootstrapper=kubeadm

Install Kata Containers

Follow the instructions provided at Kata Containers Installation Guide

Create a Sandbox using the kata-qemu runtimeClassName

Apply the kustomize overlay to inject runtimeClassName: kata-qemu to the vscode-sandbox example and apply it to the cluster:

kubectl apply -k overlays/kata

Validate that the Pod with Kata container enabled is running:

$ kubectl wait --for=condition=Ready sandbox sandbox-example
$ kubectl get pods -o jsonpath=$'{range .items[*]}{.metadata.name}: {.spec.runtimeClassName}\n{end}'

Accessing VSCode

1. Wait for VSCode to Start

The sandbox-example pod runs an initialization process (envbuilder) that clones the repository and installs dependencies before starting VSCode. You must wait for this process to finish.

Watch the logs until you see HTTP server listening:

# Wait for output similar to:
$ kubectl logs -f sandbox-example

[2025-...] info  Wrote default config file to /root/.config/code-server/config.yaml
[2025-...] info  HTTP server listening on [http://0.0.0.0:13337/](http://0.0.0.0:13337/)
[2025-...] info    - Authentication is disabled

2. Connect to VSCode

Option A: Simple Access (Standard Runtime)

If you are running the standard example (without gVisor or Kata), you can port-forward directly to the pod.

# Forward local port 13337 to the pod
kubectl port-forward pod/sandbox-example 13337:13337

Open your browser to: http://localhost:13337 or <machine-dns>:13337

Option B: Secure Access (gVisor / Kata / Production)

If you are using gVisor or Kata Containers, direct pod port-forwarding isn’t compatible. In this case, use the Sandbox Router.

Prerequisites:

1. Deploy the Router (Required for All Modes):

   # Deploys the Deployment and Service
   kubectl apply -f ../../clients/python/agentic-sandbox-client/sandbox_router/sandbox_router.yaml
   

2. Deploy the Gateway (Production Only): If you need external access via a Public IP (GKE), apply the Gateway configuration.

   # Deploys Gateway, HTTPRoute, and HealthCheckPolicy
   kubectl apply -f ../../clients/python/agentic-sandbox-client/sandbox_router/gateway.yaml
   

For Production (via Gateway)

1. Get the Gateway IP:

export GATEWAY_IP=$(kubectl get gateway external-http-gateway -n default -o jsonpath='{.status.addresses[0].value}')
echo "Gateway IP: $GATEWAY_IP"

2. Connect: (Curl Test): You must inject the routing headers. Use curl to test:

curl -v -H "X-Sandbox-ID: sandbox-example" \
        -H "X-Sandbox-Port: 13337" \
        http://$GATEWAY_IP

3. Access via Browser (UI): To load the VSCode interface, your browser must send the routing headers.

   1. Install a header-modifying extension (e.g., ModHeader for Chrome/Edge/Firefox).
   2. Configure the extension to send:
      • X-Sandbox-ID: sandbox-example
      • X-Sandbox-Port: 13337
   3. Navigate to http://<GATEWAY_IP> (replace with the IP from step 1).

   You should see the VSCode interface load immediately.

For Local Development (via Router Tunnel)

For local development, port-forward to the Router Service (do not port-forward to the pod directly, as it’s not compatible with secure runtimes like gVisor/kata).

1. Start the Tunnel:

# Forward local 8080 to the Router Service
kubectl port-forward svc/sandbox-router-svc 8080:8080 -n default

• Access via Curl: You need to send the correct headers to route traffic to your specific sandbox. Via curl, set:

curl -v -H "X-Sandbox-ID: sandbox-example" \
        -H "X-Sandbox-Port: 13337" \
        http://localhost:8080

Getting VSCode password

If the logs indicate authentication is enabled, retrieve the password. In a separate terminal connect to the pod and get the password.

kubectl exec  sandbox-example --  cat /root/.config/code-server/config.yaml 

Use the password and connect to vscode.

Use gemini-cli

Gemini cli is preinstalled. Open a teminal in vscode and use Gemini cli.